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TCP SYN attacks - a simple solution
by rex＠staff.cs.su.oz.au 07 Oct '96

07 Oct '96

There have been several (many?) products attempting to solve the TCP SYN attack through timeouts. They watch the SYN packets, and flush ones, by doing a RESET on the connection if the third packet isn't received in time. Or letting conenctions fail by flushing the infant connection table when full. I believe this is wrong! There is, I believe, a much simpler solution. The problem is, as I see it, that the current implementations are keeping the first packet (in some form) around, as state. Instead, we want to discard all this state information, to allow us to accept more packets. Only when we have a full connection do we want to keep state information. The only piece of information we require at this early stage is the initial sequence number for our side. I propose a solution where the initial sequence number is calculated (not random), and is based on a cryptographic calculation of the senders Initial Sequence Number, the ports, and a "per boot" secret number. In this way the initial packet can be discarded, and on receipt of the third SYN packet can be recalculated. This means that initial packets, fired from random addreses will never have the third packet, and no overheads are consumed, except for the hash calculation. Since there is only one random number in the connection, the initial sequence number from the originating site, there is a higher probability of "rogue", or lost packets, but if the initial ISN was truely random this shouldn't be to much of a problem (hmmm - am I sure?). Pictorally: Host A to conenct to Host B host A (good) Host B (good) gen ISN send packet to B ---> receives packet, and ISN. uses F(ISN(A) + ports + secret) as calculated ISN for return and sends to A, discards all receives packet <---- state. as normal, and sends third packet ---> receives packet, recalculates ISN from 1st step. If it matches the ACK in the packet then this is a valid connection. The nice thing about this is that no changes have to occur on the sending side. This solution will work with current IP stacks, but will automatically reject bogus connections, and has no silly timeout on valid connections. This scheme does have implications with firewalls that base all decisions on the first packet, such as packet filtering firewalls, but then again, I don't consider them real firewalls. :-) I'm going to implement this, using boring old md5, and give it a try, but I was wondering if there are any thoughts about this as a solution? Any obvious holes I missed. Rex di Bona.

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Re: TCP SYN attacks - a simple solution
by matthew＠scruz.net 07 Oct '96

07 Oct '96

Original message <199610062314.TAA29781(a)merit.edu> From: rex(a)staff.cs.su.oz.au (Rex di Bona) Date: Oct 7, 8:10 Subject: TCP SYN attacks - a simple solution > ... > I propose a solution where the initial sequence number is calculated > (not random), and is based on a cryptographic calculation of the > senders Initial Sequence Number, the ports, and a "per boot" > secret number. In this way the initial packet can be discarded, > and on receipt of the third SYN packet can be recalculated. ... The idea has been floated before, and I believe it to be the right solution to this problem. However, I have some suggested improvements: 1. The use of a "per boot" secret number allows an attacker to poll your machine to deduce the secret, and then attack you with that knowledge. A solution to this problem is to use a rapidly changing secret, the pattern of which cannot be easily deduced, and a sliding window of acceptance. (If the hash doesn't match the current scheme, but matches the scheme we were using in the past N seconds, then accept the packet) The change interval needs to be short enough that, by the time an attacker has been able to compute the next number, the window for accepting that has closed. 2. The TCP specification allows data to ride along with the initial SYN, and requires that after the three-way handshake, that the data be presented to the application layer. One solution is to realize that very few implementations take advantage of this, and simply not accept this form of SYN. A second solution is to NOT ack the data that is riding along, but the TCP state machine definition has some holes here which may not work for all implementations. The solution of buffering those SYN's which contain data is unacceptable, because attackers will simply switch to sending SYNs with data. I believe that switching to this sort of scheme would also thwart most attacks which rely on sequence number prediction, and save memory significantly over schemes which simply increase the number of TCBs allowed. -matthew kaufman matthew(a)scruz.net ps. I've been meaning to write this entire scheme, with the enhancements I propose here, as a draft specification, but I keep getting interrupted by flooded phone rooms and the like this weekend. *sigh*

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RE: My First Denial of Service Attack..... (fwd)
by Michael Dillon 07 Oct '96

07 Oct '96

---------- Forwarded message ---------- Date: Sun, 6 Oct 1996 11:40:25 -0400 From: Dave Van Allen <dave(a)fast.net> Reply-To: inet-access(a)earth.com To: "'inet-access(a)earth.com'" <inet-access(a)earth.com> Subject: RE: My First Denial of Service Attack..... Resent-Date: Sun, 6 Oct 1996 09:38:04 -0600 (MDT) Resent-From: inet-access(a)earth.com FYI, (if it has already been mentioned, please excuse the double post, but:) The latest version of the SYN attack code published in Phrack (last weeks edition, NOT last months) has an imbedded 'ping' ever several hundred SYN packets. If you get attacked, run snoop, tcpdump or anything that captures packets, and look for the pings - they have the real source address of the sender of the SYN flood attack. Please note, obviously the code can be modified to NOT ping, but our attacker last night did not do that, and we had the name of the user, their ISP, and other info in less than 15 minutes. Best regards, - Dave Van Allen - You Tools Corporation/FASTNET(tm) dave(a)fast.net (610)954-5910 http://www.fast.net FASTNET - PA/NJ/DE Business Internet Solutions >---------- >From: Avi Freedman[SMTP:freedman@netaxs.com] >Sent: Saturday, October 05, 1996 7:37 PM >To: inet-access(a)earth.com >Subject: Re: My First Denial of Service Attack..... > >> I have a question about this - >> >> Could place an incoming ping filter denying all on your router, AND turn >> off small servers on the router? Would this work? Is there a downside to >> this? >> >> -Elroy ( elroy(a)mail.kcstar.com ) > >Not to state the obvious, but if you turn off pings into your network >then noone can ping into your network (for diagnostics etc...) > >Turning off small-servers on the router only affects things to the >router (and not ICMP pings, just presumably udp pings). > >Avi > > >============================== ISP Mailing List >============================== >Email ``unsubscribe'' to inet-access-request(a)earth.com to be removed. >Email ``subscribe'' to inet-access-request(a)earth.com to join the list. > ============================== ISP Mailing List ============================== Email ``unsubscribe'' to inet-access-request(a)earth.com to be removed. Excellent day for putting Slinkies on an escalator.

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Re: New Denial of Service Attack on Panix
by Kent W. England 05 Oct '96

05 Oct '96

At 09:09 AM 9/18/96 -0400, Guy T Almes wrote: >Kent, > I liked the rest of your message more than the first sentence. > >>> >>I wish that it were not so, but after reading the clever and insightful >>approaches to tracking down the denial-of-service perps, I am pessimistic >>about our ability to stay ahead in the escalation of this counter-counter- >>measure warfare. I think that if we were able to trace the Panix attacker >>that a future attacker would hit simultaneously from a half-dozen free >>dial-up connections with a real random number generator and synthetic >>SYNs to fool the router stat collector (or whatever it takes). I think we >>are on the short end of the technology stick here. >> I want to amend my statement a bit. While it sounds like I completely ignored Curtis' summary message from Monday, in fact, I never received any of those nanog messages and if I had, I doubt that I would have posted my original message. I faithfully read all my nanog mail and I don't understand the gaps in my receipts. It seems to me after reading Curtis' summary that servers can be modified to make the SYN flooding attacks much more difficult to accomplish. Perhaps enough so that source address filtering doesn't have the urgency of implementation and coordination that I thought before reading Curtis' note. --Kent

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RE: TCP SYN attacks
by Ted Linnenkamp 04 Oct '96

04 Oct '96

>---------- >From: Tim Bass[SMTP:bass@linux.silkroad.com] >Sent: Friday, October 04, 1996 7:58 AM >To: freedman(a)netaxs.com >Cc: nanog(a)merit.edu; iepg(a)iepg.org >Subject: Re: TCP SYN attacks > >> >> My preferred approach is to not even have to store state on any >> of the embryonic connections. And to implement the fix on all >> of my hosts. And customers can implement it in a firewall, if >> they choose (and have boxes which can't be fixed: Win95, NT, Macs, ...). >> >> Avi >> Avi, Did you mean to state that these boxes can't be fixed (hardened against SYN attacks) by you? Ted L. My statements are my own and not of the Microsoft Corp. >

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Re: DoS, ICMP, proxies, SYNDefender
by Jeff Weisberg 04 Oct '96

04 Oct '96

| > I like the 'no-data structures until the' three way handshake | > is complete idea that Jeff posted yesterday. Guess I can | > applied this to linux.... has anyone done this? If so, | > I would rather start testing a patch to save time. | > | > Regards, | > | > Tim | | I'm quite sure I could take the code Jeff did and hack it so that | it could be applied to my vacuum cleaner if that was being SYN- | stormed... | | Jeff's a SunOS/BSD bigot as well so I doubt he'll do anything | directly re: a linux port :) correct, Jeff has no intention of porting to linux, but the changes to tcp_input are simple and easily understood. It shouldn't be too hard for someone to port. as for vacuum cleaners, in my past I once worked on a project involving networking household appliances. I still have source code, but alas, it is not TCP/IP based.... :-) --jeff

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Re: DoS, ICMP, proxies, SYNDefender
by Jeff Weisberg 04 Oct '96

04 Oct '96

| > > This is not the right forum to discuss TCP internals nor is it the right | > > forum to discuss building hardened kernels | | It's in-scope for nanog to the extent that published results and | host-mod procedures are something we may want to pass on to publishers, | but probably some of the TCP/IP newsgroups would be a better place | than nanog. Perhaps inet-access? Inet-access at least has so much | random garbage flowing by that people are used to responding only | to what they are interested in. definately *not* inet-access. alt.pictures.cats.naked would be a better place than "finger-on-'d'key.s0.g0", er inet-access.... --jeff

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The Cidr Report
by Tony Bates 04 Oct '96

04 Oct '96

This is an auto-generated mail on Fri Oct 4 12:00:00 PDT 1996 It is not checked before it leaves my workstation. However, hopefully you will find this report interesting and will take the time to look through this to see if you can improve the amount of aggregation you perform. The report is split into sections: 0) General Status List the route table history for the last week, list any possibly bogus routes seen and give some status on ASes. 1) Gains by aggregating at the origin AS level This lists the "Top 30" players who if they decided to aggregate their announced classful prefixes at the origin AS level could make a significant difference in the reduction of the current size of the Internet routing table. This calculation does not take into account the inclusion of holes when forming an aggregate so it is possible even larger reduction should be possible. 2) Weekly Delta A summary of the last weeks changes in terms of withdrawn and added routes. Please note that this is only a snapshot but does give some indication of ASes participating in CIDR. Clearly, it is generally a good thing to see a large amont of withdrawls. 3) Interesting aggregates Interesting here means not an aggregate made as a set of classful routes. Thanks to xara.net for giving me access to their routing tables once a day. Please send any comments about this report directly to me. In the future I hope to put some (or most) of this report up on the web. ------------------------------------------------------------------------------ CIDR REPORT for 04Oct96 0) General Status Table History ------------- Date Prefixes 280996 42250 290996 42040 300996 42235 011096 42228 021096 42249 031096 42109 041096 41894 Possible Bogus Routes --------------------- *** Bogus 211.199.11.0 from AS6176 AS Summary ---------- Number of ASes in routing system: 1649 Number of ASes announcing only one prefix: 649 (340 cidr, 309 classful) Largest number of cidr routes: 518 announced by AS3561 Largest number of classful routes: 1273 announced by AS174 1) Gains by aggregating at the origin AS level --- 04Oct96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS279 830 482 348 41.9% SURAnet Southern AS AS174 1273 927 346 27.2% Performance Systems International AS2493 768 489 279 36.3% i*internet AS3602 588 331 257 43.7% Intergrated Network Services Inc. AS3397 302 98 204 67.5% EMI-AS AS3749 230 48 182 79.1% Tennessee Board of Regents AS2048 332 152 180 54.2% State of Louisiana/Office of Tele AS1 424 279 145 34.2% BBN Planet backbone AS1691 294 157 137 46.6% ANS-BLK1 AS3804 371 235 136 36.7% WorldLinx 3 AS86 374 239 135 36.1% SURAnet Northern AS AS1790 368 249 119 32.3% SprintLink Washington D.C. AS568 359 252 107 29.8% JIS (Joint Interconnection Servic AS719 554 455 99 17.9% LANLINK autonomous system AS560 417 321 96 23.0% BBN Planet, New England Region (N AS2386 230 135 95 41.3% INS-AS AS2704 263 183 80 30.4% HOOKUP-NET-A AS813 233 162 71 30.5% UUNET Canada (ASN-UUNETCA-AS1) AS3819 98 29 69 70.4% SIGNET AS3450 112 46 66 58.9% UTK AS225 123 60 63 51.2% University of Virginia (VIRnet) AS1791 209 146 63 30.1% SprintLink Fort Worth TX AS855 127 65 62 48.8% NBTel AS1785 288 227 61 21.2% NYSERNet Backbone AS5650 163 104 59 36.2% Electric Lightwave Inc. and XMiss AS2711 111 52 59 53.2% SUNBELT-AS AS3603 96 39 57 59.4% CETCOL - Uniandes AS2871 140 83 57 40.7% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N AS3996 106 52 54 50.9% FIRN --- 03Oct96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS174 1270 921 349 27.5% Performance Systems International AS279 830 487 343 41.3% SURAnet Southern AS AS2493 764 486 278 36.4% i*internet AS3602 586 333 253 43.2% Intergrated Network Services Inc. AS3397 302 98 204 67.5% EMI-AS AS3749 261 61 200 76.6% Tennessee Board of Regents AS2048 337 154 183 54.3% State of Louisiana/Office of Tele AS1 432 289 143 33.1% BBN Planet backbone AS1691 295 158 137 46.4% ANS-BLK1 AS3804 372 236 136 36.6% WorldLinx 3 AS86 370 236 134 36.2% SURAnet Northern AS AS568 361 253 108 29.9% JIS (Joint Interconnection Servic AS262 252 152 100 39.7% JVNC-II-AS AS719 551 453 98 17.8% LANLINK autonomous system AS560 416 320 96 23.1% BBN Planet, New England Region (N AS2386 230 135 95 41.3% INS-AS AS1790 340 252 88 25.9% SprintLink Washington D.C. AS2704 265 185 80 30.2% HOOKUP-NET-A AS97 288 211 77 26.7% JvNCnet AS813 233 163 70 30.0% UUNET Canada (ASN-UUNETCA-AS1) AS3819 98 29 69 70.4% SIGNET AS3450 111 46 65 58.6% UTK AS225 123 60 63 51.2% University of Virginia (VIRnet) AS1791 209 146 63 30.1% SprintLink Fort Worth TX AS1785 286 226 60 21.0% NYSERNet Backbone AS2711 111 52 59 53.2% SUNBELT-AS AS855 125 67 58 46.4% NBTel AS5650 160 102 58 36.2% Electric Lightwave Inc. and XMiss AS2871 140 83 57 40.7% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N --- 02Oct96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS174 1264 922 342 27.1% Performance Systems International AS279 822 483 339 41.2% SURAnet Southern AS AS2493 762 485 277 36.4% i*internet AS3602 584 332 252 43.2% Intergrated Network Services Inc. AS3397 302 98 204 67.5% EMI-AS AS2048 339 153 186 54.9% State of Louisiana/Office of Tele AS3749 239 63 176 73.6% Tennessee Board of Regents AS1 433 288 145 33.5% BBN Planet backbone AS1691 293 156 137 46.8% ANS-BLK1 AS3804 372 236 136 36.6% WorldLinx 3 AS86 344 235 109 31.7% SURAnet Northern AS AS568 359 251 108 30.1% JIS (Joint Interconnection Servic AS262 261 162 99 37.9% JVNC-II-AS AS719 552 454 98 17.8% LANLINK autonomous system AS560 416 321 95 22.8% BBN Planet, New England Region (N AS2386 231 136 95 41.1% INS-AS AS1790 340 252 88 25.9% SprintLink Washington D.C. AS97 298 216 82 27.5% JvNCnet AS2704 264 185 79 29.9% HOOKUP-NET-A AS813 238 168 70 29.4% UUNET Canada (ASN-UUNETCA-AS1) AS3819 98 29 69 70.4% SIGNET AS3450 111 46 65 58.6% UTK AS225 123 60 63 51.2% University of Virginia (VIRnet) AS1791 210 147 63 30.0% SprintLink Fort Worth TX AS3996 112 53 59 52.7% FIRN AS2711 111 52 59 53.2% SUNBELT-AS AS855 124 66 58 46.8% NBTel AS1785 284 226 58 20.4% NYSERNet Backbone AS2871 141 84 57 40.4% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N --- 01Oct96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS174 1269 922 347 27.3% Performance Systems International AS279 833 492 341 40.9% SURAnet Southern AS AS2493 759 482 277 36.5% i*internet AS3602 583 331 252 43.2% Intergrated Network Services Inc. AS3397 302 98 204 67.5% EMI-AS AS3749 257 64 193 75.1% Tennessee Board of Regents AS2048 317 152 165 52.1% State of Louisiana/Office of Tele AS4230 362 220 142 39.2% Embratel Brazil AS1 430 288 142 33.0% BBN Planet backbone AS3804 379 238 141 37.2% WorldLinx 3 AS86 368 233 135 36.7% SURAnet Northern AS AS1691 279 159 120 43.0% ANS-BLK1 AS568 363 254 109 30.0% JIS (Joint Interconnection Servic AS719 548 452 96 17.5% LANLINK autonomous system AS2386 230 136 94 40.9% INS-AS AS1790 340 252 88 25.9% SprintLink Washington D.C. AS2704 264 183 81 30.7% HOOKUP-NET-A AS560 398 322 76 19.1% BBN Planet, New England Region (N AS813 233 163 70 30.0% UUNET Canada (ASN-UUNETCA-AS1) AS3819 98 29 69 70.4% SIGNET AS3450 110 47 63 57.3% UTK AS1791 210 147 63 30.0% SprintLink Fort Worth TX AS2711 109 50 59 54.1% SUNBELT-AS AS855 124 66 58 46.8% NBTel AS3996 107 49 58 54.2% FIRN AS1785 284 226 58 20.4% NYSERNet Backbone AS2871 140 83 57 40.7% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N AS5650 153 98 55 35.9% Electric Lightwave Inc. and XMiss AS3603 88 34 54 61.4% CETCOL - Uniandes --- 30Sep96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS719 1012 600 412 40.7% LANLINK autonomous system AS174 1262 920 342 27.1% Performance Systems International AS279 833 498 335 40.2% SURAnet Southern AS AS2493 757 480 277 36.6% i*internet AS3602 587 334 253 43.1% Intergrated Network Services Inc. AS3397 300 98 202 67.3% EMI-AS AS3749 259 66 193 74.5% Tennessee Board of Regents AS2048 338 156 182 53.8% State of Louisiana/Office of Tele AS1 433 288 145 33.5% BBN Planet backbone AS4230 360 219 141 39.2% Embratel Brazil AS3804 378 237 141 37.3% WorldLinx 3 AS1691 294 157 137 46.6% ANS-BLK1 AS86 363 238 125 34.4% SURAnet Northern AS AS568 364 256 108 29.7% JIS (Joint Interconnection Servic AS2386 230 136 94 40.9% INS-AS AS2704 261 183 78 29.9% HOOKUP-NET-A AS1790 323 245 78 24.1% SprintLink Washington D.C. AS560 399 323 76 19.0% BBN Planet, New England Region (N AS3819 98 29 69 70.4% SIGNET AS813 229 164 65 28.4% UUNET Canada (ASN-UUNETCA-AS1) AS225 125 61 64 51.2% University of Virginia (VIRnet) AS3450 112 49 63 56.2% UTK AS1791 209 146 63 30.1% SprintLink Fort Worth TX AS1785 287 227 60 20.9% NYSERNet Backbone AS3996 110 51 59 53.6% FIRN AS2711 110 51 59 53.6% SUNBELT-AS AS855 122 65 57 46.7% NBTel AS2871 140 83 57 40.7% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N AS5650 142 91 51 35.9% Electric Lightwave Inc. and XMiss --- 29Sep96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS719 1011 601 410 40.6% LANLINK autonomous system AS279 853 513 340 39.9% SURAnet Southern AS AS174 1254 915 339 27.0% Performance Systems International AS2493 757 480 277 36.6% i*internet AS3602 586 333 253 43.2% Intergrated Network Services Inc. AS3397 300 98 202 67.3% EMI-AS AS3749 258 65 193 74.8% Tennessee Board of Regents AS2048 321 148 173 53.9% State of Louisiana/Office of Tele AS1 432 287 145 33.6% BBN Planet backbone AS4230 360 219 141 39.2% Embratel Brazil AS3804 378 237 141 37.3% WorldLinx 3 AS1691 294 157 137 46.6% ANS-BLK1 AS86 364 236 128 35.2% SURAnet Northern AS AS568 365 256 109 29.9% JIS (Joint Interconnection Servic AS2386 230 136 94 40.9% INS-AS AS1790 322 244 78 24.2% SprintLink Washington D.C. AS2704 260 183 77 29.6% HOOKUP-NET-A AS560 386 310 76 19.7% BBN Planet, New England Region (N AS3819 100 31 69 69.0% SIGNET AS813 225 160 65 28.9% UUNET Canada (ASN-UUNETCA-AS1) AS225 125 61 64 51.2% University of Virginia (VIRnet) AS3450 112 49 63 56.2% UTK AS1791 193 130 63 32.6% SprintLink Fort Worth TX AS1785 287 227 60 20.9% NYSERNet Backbone AS3996 110 51 59 53.6% FIRN AS2711 110 51 59 53.6% SUNBELT-AS AS855 122 65 57 46.7% NBTel AS2871 140 83 57 40.7% Internet Services GmbH & Co AS839 90 35 55 61.1% North West Territories Regional N AS721 306 252 54 17.6% DLA-ASNBLOCK-AS --- 28Sep96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS719 1011 601 410 40.6% UNKNOWN AS174 1260 918 342 27.1% UNKNOWN AS279 849 508 341 40.2% UNKNOWN AS2493 749 473 276 36.8% UNKNOWN AS3602 587 334 253 43.1% UNKNOWN AS3397 300 98 202 67.3% EMI-AS AS3749 258 65 193 74.8% Tennessee Board of Regents AS2048 340 153 187 55.0% State of Louisiana/Office of Tele AS1 430 285 145 33.7% UNKNOWN AS4230 360 219 141 39.2% UNKNOWN AS3804 379 238 141 37.2% UNKNOWN AS1691 294 157 137 46.6% ANS-BLK1 AS86 366 231 135 36.9% UNKNOWN AS568 365 256 109 29.9% UNKNOWN AS2386 231 136 95 41.1% INS-AS AS2704 264 184 80 30.3% HOOKUP-NET-A AS1790 323 245 78 24.1% SprintLink Washington D.C. AS560 397 323 74 18.6% UNKNOWN AS3819 98 29 69 70.4% SIGNET AS813 230 163 67 29.1% UUNET Canada (ASN-UUNETCA-AS1) AS225 125 61 64 51.2% University of Virginia (VIRnet) AS3450 112 49 63 56.2% UTK AS1791 208 145 63 30.3% SprintLink Fort Worth TX AS1785 287 227 60 20.9% NYSERNet Backbone AS3996 110 51 59 53.6% FIRN AS2711 110 51 59 53.6% SUNBELT-AS AS855 124 66 58 46.8% NBTel AS839 90 35 55 61.1% North West Territories Regional N AS721 312 258 54 17.3% DLA-ASNBLOCK-AS AS2871 131 77 54 41.2% Internet Services GmbH & Co --- 27Sep96 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS719 1011 601 410 40.6% LANLINK autonomous system AS174 1268 924 344 27.1% Performance Systems International AS279 850 508 342 40.2% SURAnet Southern AS AS2493 756 479 277 36.6% i*internet AS3602 586 335 251 42.8% Intergrated Network Services Inc. AS3397 300 98 202 67.3% EMI-AS AS3749 273 73 200 73.3% Tennessee Board of Regents AS2048 342 153 189 55.3% State of Louisiana/Office of Tele AS1 426 281 145 34.0% BBN Planet backbone AS86 379 236 143 37.7% SURAnet Northern AS AS3804 384 241 143 37.2% WorldLinx 3 AS1691 294 157 137 46.6% ANS-BLK1 AS4230 350 214 136 38.9% Embratel Brazil AS568 370 259 111 30.0% JIS (Joint Interconnection Servic AS2386 231 136 95 41.1% INS-AS AS1790 335 250 85 25.4% SprintLink Washington D.C. AS2704 266 186 80 30.1% HOOKUP-NET-A AS721 335 259 76 22.7% DLA-ASNBLOCK-AS AS3215 132 57 75 56.8% RAIN AS560 399 325 74 18.5% BBN Planet, New England Region (N AS3819 98 29 69 70.4% SIGNET AS225 127 61 66 52.0% University of Virginia (VIRnet) AS813 228 164 64 28.1% UUNET Canada (ASN-UUNETCA-AS1) AS3450 110 47 63 57.3% UTK AS3996 113 51 62 54.9% FIRN AS1791 199 137 62 31.2% SprintLink Fort Worth TX AS1785 285 225 60 21.1% NYSERNet Backbone AS2711 109 50 59 54.1% SUNBELT-AS AS855 125 67 58 46.4% NBTel AS2871 139 82 57 41.0% Internet Services GmbH & Co 2) Weekly Delta This a daily snapshot of changes in classful routes being withdrawn and added. the deltas are calculated over a rolling 7 day period. Please bear in mind this is purely a "snapshot" and a large flucuation could be caused by a connectivity problem for example. However, this does give some indication of service providers that are moving to classless routing. Top 20 Withdrawn Routes from 27Sep96 to 04Oct96 -457 AS719 LANLINK autonomous system -221 AS4230 Embratel Brazil -98 AS3215 RAIN -61 AS262 JVNC-II-AS -49 AS721 DLA-ASNBLOCK-AS -48 AS2551 NETCOM On-line Communication Serv -43 AS3749 Tennessee Board of Regents -32 AS1275 DFN-IP -27 AS2686 Autonomous System number for IBM -25 AS3492 ATLANTA -24 AS2520 JNIC-ASN -20 AS279 SURAnet Southern AS -18 AS3733 GULF-COAST -17 AS600 OARnet AS -16 AS786 The JANET IP Service -15 AS6407 Internet Canada Corporation -14 AS2277 ECUANET -13 AS3804 WorldLinx 3 -11 AS568 JIS (Joint Interconnection Servic -10 AS6401 eConnect Top 20 Added Routes from 27Sep96 to 04Oct96 169 AS1717 RENATER 122 AS5650 Electric Lightwave Inc. and XMiss 87 AS97 JvNCnet 82 AS1794 SprintLink Pennsauken NJ 59 AS2941 CSCNS-AS 41 AS3301 TeliaNet Sweden 33 AS1790 SprintLink Washington D.C. 30 AS6174 SPRINTLINK8 21 AS4006 NetRail, Inc. 20 AS1795 SprintLink Anaheim CA 19 AS297 Nasa Science Network (FIX-East) 18 AS560 BBN Planet, New England Region (N 16 AS4433 ACCESS-ONE 14 AS376 RISQ Backbone 12 AS5755 QNETIX-AS 11 AS3493 INTERLINK 10 AS1791 SprintLink Fort Worth TX 9 AS3603 CETCOL - Uniandes 8 AS6203 ISDN-Net Inc. 6 AS3252 "Relcom-Ukraine" Ltd. TS network 3) Interesting aggregates List of possibly interesting aggregates --------------------------------------- aggregate origin-AS AS Description 9.2.0.0/16 AS1747 IBM Watson, Yorktown Heights, 9.20.0.0/17 AS2686 Autonomous System number for I 9.67.0.0/19 AS3561 MCI 57.12.0.0/16 AS5384 Etisalat Emirates Internet 128.145.228.0/24 AS174 Performance Systems Internatio 128.188.1.0/24 AS560 BBN Planet, New England Region 130.168.105.0/24 AS1270 EUnet Germany 130.168.115.0/24 AS1270 EUnet Germany 130.168.125.0/24 AS1270 EUnet Germany 130.188.2.0/24 AS565 VTT autonomous system 130.188.3.0/24 AS565 VTT autonomous system 130.188.150.0/24 AS565 VTT autonomous system 130.188.252.0/24 AS565 VTT autonomous system 130.205.64.0/18 AS3561 MCI 130.252.178.0/24 AS1321 ANS San Francisco - DNSS 11 131.114.192.0/18 AS2598 Consiglio Nazionale delle Rice 131.115.211.0/24 AS3301 TeliaNet Sweden 131.115.254.0/24 AS3301 TeliaNet Sweden 131.117.0.0/17 AS559 SWITCH, Swiss Academic and Res 132.235.204.0/24 AS3561 MCI 134.6.160.0/22 AS2706 HKSUPER 134.6.180.0/24 AS2706 HKSUPER 134.33.100.0/24 AS701 Alternet 134.129.0.0/17 AS6263 NDIN 134.129.128.0/17 AS6263 NDIN 134.198.8.0/21 AS3593 Eastern Pennsylvania Internet 134.198.16.0/21 AS3593 Eastern Pennsylvania Internet 134.198.24.0/21 AS3593 Eastern Pennsylvania Internet 134.198.32.0/21 AS3593 Eastern Pennsylvania Internet 134.198.40.0/21 AS3593 Eastern Pennsylvania Internet 134.198.48.0/21 AS3593 Eastern Pennsylvania Internet 134.198.56.0/21 AS3593 Eastern Pennsylvania Internet 134.198.64.0/21 AS3593 Eastern Pennsylvania Internet 134.198.72.0/21 AS3593 Eastern Pennsylvania Internet 134.198.96.0/21 AS3593 Eastern Pennsylvania Internet 134.198.168.0/21 AS3593 Eastern Pennsylvania Internet 134.198.192.0/21 AS3593 Eastern Pennsylvania Internet 134.198.232.0/21 AS3593 Eastern Pennsylvania Internet 134.198.240.0/21 AS3593 Eastern Pennsylvania Internet 134.204.14.0/24 AS3561 MCI 134.204.176.0/24 AS3561 MCI 134.241.109.0/24 AS560 BBN Planet, New England Region 135.14.65.0/24 AS3111 Internet Direct Inc. (ASN-DIRE 135.16.150.0/24 AS560 BBN Planet, New England Region 135.37.2.0/24 AS3561 MCI 135.37.4.0/24 AS3561 MCI 135.37.10.0/24 AS3561 MCI 135.37.14.0/24 AS3561 MCI 135.40.66.0/24 AS3561 MCI 136.140.9.0/24 AS3561 MCI 137.62.197.0/24 AS1794 SprintLink Pennsauken NJ 138.95.80.0/24 AS701 Alternet 138.108.100.0/24 AS3561 MCI 138.182.252.0/24 AS5855 Secretary of the Navy 138.182.254.0/24 AS5855 Secretary of the Navy 139.46.35.0/24 AS560 BBN Planet, New England Region 139.61.102.0/24 AS3111 Internet Direct Inc. (ASN-DIRE 139.61.103.0/24 AS3111 Internet Direct Inc. (ASN-DIRE 139.162.128.0/17 AS1136 Unisource Internet Service NL 140.10.12.0/24 AS701 Alternet 140.188.86.0/24 AS174 Performance Systems Internatio 140.188.129.0/24 AS174 Performance Systems Internatio 140.188.198.0/24 AS174 Performance Systems Internatio 140.231.44.0/24 AS3561 MCI 141.227.111.0/24 AS2529 Demon Internet Ltd 142.77.19.0/24 AS813 UUNET Canada (ASN-UUNETCA-AS1) 142.77.248.0/24 AS813 UUNET Canada (ASN-UUNETCA-AS1) 143.222.116.0/24 AS3407 Interpath 143.252.80.0/24 AS2856 BTnet UK Regional network 144.192.181.0/24 AS4200 AGIS (Apex Global Information 144.199.161.0/24 AS1238 ICM Malaysia (MIMOS) connectee 144.228.143.0/24 AS1792 SprintLink Stockton CA 145.17.100.0/24 AS2856 BTnet UK Regional network 145.72.32.0/19 AS5484 BT Netherlands Regional Servic 145.72.64.0/19 AS5484 BT Netherlands Regional Servic 145.246.16.0/24 AS2856 BTnet UK Regional network 145.246.17.0/24 AS2856 BTnet UK Regional network 145.247.151.0/24 AS2120 DAXnet (Tele 3) 145.247.152.0/24 AS2120 DAXnet (Tele 3) 145.247.153.0/24 AS2120 DAXnet (Tele 3) 145.247.154.0/24 AS2120 DAXnet (Tele 3) 145.247.155.0/24 AS2120 DAXnet (Tele 3) 145.247.156.0/24 AS2120 DAXnet (Tele 3) 145.247.157.0/24 AS2120 DAXnet (Tele 3) 145.247.158.0/24 AS2120 DAXnet (Tele 3) 145.247.159.0/24 AS2120 DAXnet (Tele 3) 145.247.160.0/24 AS2120 DAXnet (Tele 3) 145.247.161.0/24 AS2120 DAXnet (Tele 3) 145.247.162.0/24 AS2120 DAXnet (Tele 3) 145.247.163.0/24 AS2120 DAXnet (Tele 3) 145.247.164.0/24 AS2120 DAXnet (Tele 3) 145.247.165.0/24 AS2120 DAXnet (Tele 3) 145.247.166.0/24 AS2120 DAXnet (Tele 3) 145.247.167.0/24 AS2120 DAXnet (Tele 3) 145.247.168.0/24 AS2120 DAXnet (Tele 3) 145.247.169.0/24 AS2120 DAXnet (Tele 3) 145.247.170.0/24 AS2120 DAXnet (Tele 3) 145.248.112.0/24 AS2706 HKSUPER 145.248.155.0/24 AS2706 HKSUPER 145.248.157.0/24 AS2706 HKSUPER 145.248.159.0/24 AS2706 HKSUPER 145.248.161.0/24 AS2706 HKSUPER 145.248.165.0/24 AS2706 HKSUPER 146.75.251.0/24 AS3301 TeliaNet Sweden 146.75.253.0/24 AS1257 SWIPnet Swedish IP Network 146.75.254.0/24 AS3301 TeliaNet Sweden 147.85.21.0/24 AS3951 ICONNET 147.85.25.0/24 AS3951 ICONNET 147.85.39.0/24 AS3951 ICONNET 147.85.44.0/24 AS3951 ICONNET 147.85.51.0/24 AS3951 ICONNET 147.85.115.0/24 AS3951 ICONNET 147.151.171.0/24 AS6669 BT Spanish Regional IP network 147.160.0.0/17 AS3561 MCI 147.160.128.0/18 AS3561 MCI 147.160.192.0/20 AS3561 MCI 147.160.208.0/20 AS3561 MCI 147.160.224.0/20 AS3561 MCI 147.160.224.0/19 AS3561 MCI 147.206.20.0/24 AS3561 MCI 148.59.221.0/24 AS2015 Msen, Inc. 148.59.227.0/24 AS2015 Msen, Inc. 148.59.232.0/24 AS2015 Msen, Inc. 148.59.242.0/24 AS2015 Msen, Inc. 148.59.247.0/24 AS2015 Msen, Inc. 148.94.210.0/24 AS5714 EDS-WEB 148.185.45.0/24 AS1849 PIPEX, Public IP EXchange 148.252.1.0/24 AS1849 PIPEX, Public IP EXchange 149.20.4.0/24 AS1239 SprintLink Backbone 149.20.64.0/24 AS701 Alternet 149.212.64.0/20 AS1759 Telecom Finland iNET 150.100.52.0/24 AS1792 SprintLink Stockton CA 150.185.128.0/18 AS1800 ICM-Atlantic 150.185.192.0/18 AS1800 ICM-Atlantic 151.185.7.0/24 AS279 SURAnet Southern AS 151.185.10.0/24 AS279 SURAnet Southern AS 152.129.186.0/24 AS4478 PNET-STL 152.163.199.0/24 AS2056 AOL-AS 152.163.200.0/24 AS2056 AOL-AS 152.163.231.0/24 AS2056 AOL-AS 152.163.232.0/23 AS2056 AOL-AS 152.163.234.0/23 AS2056 AOL-AS 152.179.0.0/17 AS1321 ANS San Francisco - DNSS 11 152.187.0.0/17 AS1321 ANS San Francisco - DNSS 11 153.2.164.0/24 AS3561 MCI 155.39.191.0/24 AS2685 IGN OpenNet - US 155.134.60.0/24 AS701 Alternet 155.140.124.0/24 AS1849 PIPEX, Public IP EXchange 155.173.244.0/24 AS3561 MCI 155.203.254.0/24 AS3561 MCI 155.229.176.0/22 AS7045 UNKNOWN 155.229.176.0/21 AS7045 UNKNOWN 156.46.0.0/17 AS4550 Alpha.net Corporation (ASN-AN- 156.46.128.0/17 AS4550 Alpha.net Corporation (ASN-AN- 156.51.204.0/24 AS3301 TeliaNet Sweden 156.114.200.0/24 AS2529 Demon Internet Ltd 157.184.150.0/24 AS1330 ANS St. Louis - DNSS 83 157.232.100.0/24 AS3561 MCI 158.43.64.184/30 AS6757 Mercury Communications Ltd 158.43.200.0/24 AS701 Alternet 158.118.51.0/24 AS701 Alternet 158.155.24.0/22 AS1221 AARNET-AS 158.174.254.0/24 AS2856 BTnet UK Regional network 159.24.7.0/24 AS4286 IMCI 159.87.34.0/24 AS200 BBN Planet Western Region 159.179.0.0/24 AS3561 MCI 159.197.158.0/23 AS2529 Demon Internet Ltd 159.245.84.0/22 AS1849 PIPEX, Public IP EXchange 159.245.104.0/22 AS1849 PIPEX, Public IP EXchange 160.92.129.0/24 AS2917 OLEANE - PIPEX International 160.104.0.0/17 AS701 Alternet 160.104.128.0/17 AS1290 PSINet UK Ltd. 161.6.0.0/17 AS3561 MCI 161.6.128.0/17 AS3561 MCI 161.22.0.0/24 AS1790 SprintLink Washington D.C. 161.51.224.0/20 AS1849 PIPEX, Public IP EXchange 161.52.192.0/19 AS2845 SUNET-LUND 161.120.6.0/24 AS3561 MCI 161.223.220.0/22 AS1 BBN Planet backbone 161.223.224.0/24 AS1 BBN Planet backbone 162.17.253.0/24 AS174 Performance Systems Internatio 162.81.141.0/24 AS3561 MCI 163.12.0.0/23 AS3576 PREPnet-EAST 163.12.5.0/24 AS3576 PREPnet-EAST 163.12.16.0/22 AS3576 PREPnet-EAST 163.12.21.0/24 AS3576 PREPnet-EAST 163.12.22.0/24 AS3576 PREPnet-EAST 163.12.23.0/24 AS3576 PREPnet-EAST 163.12.24.0/21 AS3576 PREPnet-EAST 163.12.32.0/19 AS3576 PREPnet-EAST 163.12.64.0/20 AS3576 PREPnet-EAST 163.12.81.0/24 AS3576 PREPnet-EAST 163.12.84.0/22 AS3576 PREPnet-EAST 163.12.88.0/21 AS3576 PREPnet-EAST 163.12.96.0/19 AS3576 PREPnet-EAST 163.12.128.0/21 AS3576 PREPnet-EAST 163.12.136.0/22 AS3576 PREPnet-EAST 163.12.144.0/20 AS3576 PREPnet-EAST 163.12.160.0/19 AS3576 PREPnet-EAST 163.12.192.0/21 AS3576 PREPnet-EAST 163.12.240.0/20 AS3576 PREPnet-EAST 163.49.131.0/24 AS3561 MCI 163.49.132.0/22 AS3561 MCI 163.49.136.0/22 AS3561 MCI 163.49.140.0/23 AS3561 MCI 163.49.142.0/24 AS3561 MCI 163.168.212.0/24 AS3303 Unisource Business Networks (S 163.249.43.0/24 AS3739 NEWNET 163.249.53.0/24 AS3739 NEWNET 163.249.54.0/24 AS3739 NEWNET 163.249.57.0/24 AS3739 NEWNET 163.249.140.0/22 AS3739 NEWNET 163.249.160.0/21 AS3739 NEWNET 163.249.168.0/24 AS3739 NEWNET 163.249.169.0/24 AS3739 NEWNET 163.249.170.0/24 AS3739 NEWNET 164.53.55.0/24 AS2706 HKSUPER 164.99.56.192/26 AS2041 CRL-GATE 164.100.64.0/20 AS3561 MCI 164.100.80.0/24 AS4755 Videsh Sanchar Nigam Ltd. Indi 164.100.81.0/24 AS3561 MCI 164.100.82.0/23 AS3561 MCI 164.100.84.0/22 AS3561 MCI 164.100.88.0/21 AS3561 MCI 164.100.96.0/19 AS3561 MCI 164.100.167.0/24 AS3561 MCI 164.100.199.0/24 AS4755 Videsh Sanchar Nigam Ltd. Indi 164.103.3.0/24 AS3561 MCI 164.224.208.0/20 AS5855 Secretary of the Navy 165.108.130.0/24 AS3561 MCI 165.108.130.0/23 AS3561 MCI 165.108.132.0/22 AS3561 MCI 165.108.136.0/21 AS3561 MCI 165.108.144.0/22 AS3561 MCI 165.108.148.0/23 AS3561 MCI 165.113.197.0/24 AS6006 UNKNOWN 165.113.198.0/24 AS6006 UNKNOWN 165.113.199.0/24 AS6006 UNKNOWN 165.113.211.0/24 AS6006 UNKNOWN 165.113.219.0/24 AS6006 UNKNOWN 165.166.123.0/24 AS3561 MCI 165.215.64.0/18 AS4183 CompuServe, Incorporated 165.215.191.0/24 AS5090 CWI-NYD 165.247.33.0/24 AS5696 Primary AS for GoodNet 166.38.40.0/24 AS3561 MCI 166.147.0.0/18 AS3561 MCI 166.147.64.0/18 AS3561 MCI 166.147.128.0/18 AS3561 MCI 166.147.192.0/18 AS3561 MCI 166.150.0.0/18 AS3561 MCI 166.150.64.0/18 AS3561 MCI 166.150.128.0/18 AS3561 MCI 166.150.192.0/18 AS3561 MCI 166.151.0.0/18 AS3561 MCI 166.151.64.0/18 AS3561 MCI 166.151.128.0/18 AS3561 MCI 166.151.192.0/18 AS3561 MCI 167.72.128.0/24 AS3561 MCI 167.77.32.0/24 AS3561 MCI 167.105.232.0/24 AS3561 MCI 167.170.6.0/23 AS3313 I.Net S.p.A. 167.170.32.0/23 AS3313 I.Net S.p.A. 167.208.125.0/24 AS3561 MCI 168.14.1.0/24 AS3561 MCI 168.14.2.0/23 AS3561 MCI 168.14.4.0/22 AS3561 MCI 168.14.8.0/21 AS3561 MCI 168.14.16.0/20 AS3561 MCI 168.175.70.0/24 AS3561 MCI 168.175.170.0/24 AS3561 MCI 168.175.171.0/24 AS3561 MCI 168.175.172.0/24 AS3561 MCI 168.224.128.0/24 AS2856 BTnet UK Regional network 168.247.253.0/24 AS174 Performance Systems Internatio 168.247.254.0/24 AS174 Performance Systems Internatio 169.132.80.0/24 AS5000 IDT Corporation 169.137.170.0/24 AS3407 Interpath 169.200.1.0/24 AS3561 MCI 170.115.249.0/24 AS4969 Net Access 170.194.51.0/24 AS1849 PIPEX, Public IP EXchange 170.215.192.0/20 AS5650 Electric Lightwave Inc. and XM 171.25.128.0/20 AS3301 TeliaNet Sweden 171.25.144.0/21 AS3301 TeliaNet Sweden 171.25.152.0/21 AS3301 TeliaNet Sweden 171.30.170.0/24 AS2856 BTnet UK Regional network 192.103.70.0/26 AS1673 ANS-BLK1 192.103.74.0/27 AS1673 ANS-BLK1 194.6.82.88/30 AS6757 Mercury Communications Ltd 194.23.1.36/30 AS3305 Internet Service Provider back 194.178.245.32/28 AS5417 Demon Internet Ltd 194.237.174.0/29 AS3301 TeliaNet Sweden 194.237.174.8/29 AS3301 TeliaNet Sweden 194.237.174.32/27 AS3308 TeliaNet Denmark 195.38.9.6/32 AS6739 Autonomous System number for B 198.83.24.0/26 AS1673 ANS-BLK1 198.83.47.0/26 AS1673 ANS-BLK1 198.83.195.0/26 AS1673 ANS-BLK1 198.83.209.0/26 AS1673 ANS-BLK1 198.83.210.0/26 AS1673 ANS-BLK1 199.99.247.32/27 AS174 Performance Systems Internatio 199.221.28.0/26 AS1673 ANS-BLK1 199.221.38.0/27 AS1673 ANS-BLK1 199.221.47.0/25 AS1673 ANS-BLK1 199.222.34.0/26 AS1673 ANS-BLK1 199.233.98.0/25 AS6082 MAI Network Services 199.233.98.128/25 AS6082 MAI Network Services 202.50.137.64/27 AS2687 OpenNet-AP 204.148.62.0/26 AS1673 ANS-BLK1 204.148.68.0/26 AS1673 ANS-BLK1 204.151.106.0/26 AS1673 ANS-BLK1 204.151.152.0/26 AS1673 ANS-BLK1 205.156.223.176/28 AS2702 Spry AS 205.215.7.0/27 AS4006 NetRail, Inc. 205.215.7.32/27 AS4006 NetRail, Inc.

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Re: BSDI announcement about defense against syn-flooding attacks
by Rob Liebschutz 04 Oct '96

04 Oct '96

> Rob Liebschutz writes: > > It scares me to think how much effort has gone into defense against > > this one denial of service attack when there are endless possibilities > > for other ones. > > Really? I don't think enough effort has been expended... which is why I'm > expending more. This was intended to be a comparison of how much effort has already been expended with how much more is really needed. I strongly agree that more effort needs to be expended here. Both at the lab/research level and at getting the technology on every box on the Internet (and you've contributed significantly in both of those areas). Good security requires an enormous amount of ongoing effort. It's not like you secure your network and it's done. At least one good things that's happened in the last few years is that many vendors have started paying much more attention to security in their products. This really helps in the distribution effort. I've done alot of consulting in the past, and I've found at many sites that the cost of security was very hard to sell. For startup ISP's network security almost never had a line in the budget. They'd usually tell me they can't afford it. I'd tell them they can't afford to be without it. Of course alot of starup ISP's had never thought about hiring a networking person either! You just go down to the local discount computer store and buy a bunch of 10baseT hubs to plug all your computers into. One big network :-). Talk about startup ISP's (a little off topic here), I had one "WANNA-BE" ISP come to me with a T1 already installed to PBI (no CSU/DSU or router, no hubs, 1 windows 3.11 box) and they wanted me to "bring them up as an ISP". I quoted them a price, but they told me that they only had $3000 to spend. They didn't know what services they wanted to provide either. Then there were two others that came to me that had been sold NAP connections. One guy was sitting their with a single Win95 box plugged into his Cisco 75xx with a DS3 NAP connection, "Well, how do I get this thing configured?". Now he can browse the WEB on his Win 95 box at DS3 speeds:-). > > Th point is not that we have to defeat the SYN attacks. We all know by now > that the severity of that problem is, at least for modern OSes, reduced > to a tolerable level (or will be soon). But these SYN attacks are just > the precursor to other even more dangerous attacks that all share one > characteristic: forged source addresses. If we can use this event to > raise consciousness about the forged-source issue, everyone wins big. And > if we don't... well, film at 11, as we say. > > /a > Rob

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Re: TCP SYN attacks
by Richard Stiennon 04 Oct '96

04 Oct '96

At 11:37 AM 10/3/96 -0700, Ran Atkinson wrote: >>Dima Volodin writes: >>> Now can I hold my breath waiting for vendors to incorporate this stuff >>> into their products? > >At least BSDI, Sun, SGI, and HP are working on TCP SYN hardening. >(yes, cisco is also on top of things :-). > >I have no data on what might be up at other vendors. Check out the elegant solution just announced by Checkpoint: http://www.checkpoint.com/fw21/syndefender/syndefender-white.html This is a firewall solution. I like the psuedo-NAT done to adjust sequence number. ---------------------------------------------------------------------------- Richard Stiennon richards(a)netrex.com Director, Business Development http://www.netrex.com Netrex, Inc. Voice: 810-352-9643 Southfield, Michigan Fax: 810-352-2375 ----------------------------------------------------------------------------- Providing businesses and organizations with secure Internet solutions.

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