Moving fibre trunks: interruptions?
A large highway interchange is being rebuilt in Montréal (Turcot) and this requires that the CN mainline tracks out of downtown be moved a few hundred metres to the north for a couple of kilometres until it rejoins the existing alignment. Part of the contract involves the cost of moving the fibre trunks along with the tracks. (old alignment will become commercial properties). So they have new cable that goes through the new alignment and joins the old one at both ends. So they'll have hundreds of strands to splice. When doing that type of work, how much downtime can be expected for each strand? Would they typically use patch panels in central offices to move a customer to a spare strand while they splice their assigned strand to use the new cable segment (and then move traffic back to that assigned strand?). Or would they switch customers around to new strands and update their documentation on which customer is on which strand? Or do they do nothing at patch panels in COs and just take whatever time it is needed to have crews at both ends of the work site splice each strand at same time (I assume about 5 minutes outage for each strand?) Would they normally involve the customer advising them of upcoming outage? Would the folks working trackside be limited to overnight hours to make outages less significant, or do they work around the clock ?
I'd expect at least a couple of hours of outage while the cable is reconnected. When doing the move on the live cable (assuming 1 cable). There will be a splicing crew at each end of the move. They will then break a tube or ribbon at a time and splice into the new cable. Splicing unused portions of the cable and then moving patches is also done. In my experience, it's much more common to resplice on the existing strands. A large cable will take quite a while to resplice, likely more than just overnight depending on the size of the cable. Jay On Fri, Sep 1, 2017 at 1:32 PM, Jean-Francois Mezei <jfmezei_nanog@vaxination.ca> wrote:
A large highway interchange is being rebuilt in Montréal (Turcot) and this requires that the CN mainline tracks out of downtown be moved a few hundred metres to the north for a couple of kilometres until it rejoins the existing alignment.
Part of the contract involves the cost of moving the fibre trunks along with the tracks. (old alignment will become commercial properties).
So they have new cable that goes through the new alignment and joins the old one at both ends. So they'll have hundreds of strands to splice.
When doing that type of work, how much downtime can be expected for each strand?
Would they typically use patch panels in central offices to move a customer to a spare strand while they splice their assigned strand to use the new cable segment (and then move traffic back to that assigned strand?). Or would they switch customers around to new strands and update their documentation on which customer is on which strand?
Or do they do nothing at patch panels in COs and just take whatever time it is needed to have crews at both ends of the work site splice each strand at same time (I assume about 5 minutes outage for each strand?)
Would they normally involve the customer advising them of upcoming outage? Would the folks working trackside be limited to overnight hours to make outages less significant, or do they work around the clock ?
Yeah, Being somehow familiar with how things operate when it involve Quebec Govt and the Fed Govt... Expect hell. Pray for purgatory. Rejoice if it takes less than 3 months. PS: At least we have very good, and dedicated, cabling crews. =D. But yeah, there is work being done to reduce the downtime to a manageable timeframe. If not simply redundancy being added to allow for the time to splice that bad boy. ----- Alain Hebert ahebert@pubnix.net PubNIX Inc. 50 boul. St-Charles P.O. Box 26770 Beaconsfield, Quebec H9W 6G7 Tel: 514-990-5911 http://www.pubnix.net Fax: 514-990-9443 On 09/01/17 14:44, Jay Hanke wrote:
I'd expect at least a couple of hours of outage while the cable is reconnected.
When doing the move on the live cable (assuming 1 cable). There will be a splicing crew at each end of the move. They will then break a tube or ribbon at a time and splice into the new cable.
Splicing unused portions of the cable and then moving patches is also done. In my experience, it's much more common to resplice on the existing strands.
A large cable will take quite a while to resplice, likely more than just overnight depending on the size of the cable.
Jay
On Fri, Sep 1, 2017 at 1:32 PM, Jean-Francois Mezei <jfmezei_nanog@vaxination.ca> wrote:
A large highway interchange is being rebuilt in Montréal (Turcot) and this requires that the CN mainline tracks out of downtown be moved a few hundred metres to the north for a couple of kilometres until it rejoins the existing alignment.
Part of the contract involves the cost of moving the fibre trunks along with the tracks. (old alignment will become commercial properties).
So they have new cable that goes through the new alignment and joins the old one at both ends. So they'll have hundreds of strands to splice.
When doing that type of work, how much downtime can be expected for each strand?
Would they typically use patch panels in central offices to move a customer to a spare strand while they splice their assigned strand to use the new cable segment (and then move traffic back to that assigned strand?). Or would they switch customers around to new strands and update their documentation on which customer is on which strand?
Or do they do nothing at patch panels in COs and just take whatever time it is needed to have crews at both ends of the work site splice each strand at same time (I assume about 5 minutes outage for each strand?)
Would they normally involve the customer advising them of upcoming outage? Would the folks working trackside be limited to overnight hours to make outages less significant, or do they work around the clock ?
On 2017-09-01 16:12, Alain Hebert wrote:
Being somehow familiar with how things operate when it involve Quebec Govt and the Fed Govt... Expect hell. Pray for purgatory. Rejoice if it takes less than 3 months.
In this particular case, the government is giving CN new land, and once construction crews for the highway/interchange have moved on, segments are opened for CN to bring its crews to install tracks, portals, signals, track service road etc. The main contract gives CN responsability to handle the telecom under its tracks, so I assume that once CN is given access to the full length of new right of way, it will coordinate with the various telecom companies that rent space under its tracks to do the move. The move is expected in summer 2018. (during next winter, the last remaining elevated structures that block the new CN right of way will be torn down, allowing CN to then finish the work starting in spring. (it does not lay tracks in winter).
If it is in the railroad RoW they may be restricted to daylight working only. Check with your provider or OSP crew. -- "Genius might be described as a supreme capacity for getting its possessors into trouble of all kinds." -- Samuel Butler
On Sep 1, 2017, at 3:32 PM, Michael Loftis <mloftis@wgops.com> wrote:
If it is in the railroad RoW they may be restricted to daylight working only. Check with your provider or OSP crew.
Yup. Railroad work is complex just because you have to coordinate with the railroad owner and they have to be onsite for all work. The cost of going underground vs aerial is also astronomical in many cases. - Jared
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic? ________________________________ From: NANOG <nanog-bounces@nanog.org> on behalf of Jared Mauch <jared@puck.nether.net> Sent: Friday, September 1, 2017 9:37 PM To: Michael Loftis Cc: Nanog@nanog.org Subject: Re: Moving fibre trunks: interruptions?
On Sep 1, 2017, at 3:32 PM, Michael Loftis <mloftis@wgops.com> wrote:
If it is in the railroad RoW they may be restricted to daylight working only. Check with your provider or OSP crew.
Yup. Railroad work is complex just because you have to coordinate with the railroad owner and they have to be onsite for all work. The cost of going underground vs aerial is also astronomical in many cases. - Jared
On Fri, 01 Sep 2017 15:52:40 -0400, Rod Beck <rod.beck@unitedcablecompany.com> wrote:
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
Aerial is simple and fast... pull the cable through a stringer, move to the next pole and repeat; when a section (about a mile) is done, it's hoisted into the air and tied to the pole. The stringers are then moved to the next mile of poles and the process repeats. Buried stuff requires a great deal of planning, permitting, and insurance. You have to know everything that's ever been stuffed in the ground within half a mile of where you're working to avoid the inevitable cutting of something important -- gas, water, sewer, power, other telcom, even vacuum tube lines and subways. And then you need trenching gear to get stuff in the ground, and crews to come along behind to remediate the "environmental damage". (Once the conduit is in the ground, it's a trivial matter to blow whatever you need through it.)
Pretty much. Here is an example of permitting requirements for underground. Underground costs 5-12/foot (or more in urban areas) whereas aerial can be as low as $2/foot. Jared Mauch
On Sep 1, 2017, at 6:38 PM, Ricky Beam <jfbeam@gmail.com> wrote:
On Fri, 01 Sep 2017 15:52:40 -0400, Rod Beck <rod.beck@unitedcablecompany.com> wrote: I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
Aerial is simple and fast... pull the cable through a stringer, move to the next pole and repeat; when a section (about a mile) is done, it's hoisted into the air and tied to the pole. The stringers are then moved to the next mile of poles and the process repeats.
Buried stuff requires a great deal of planning, permitting, and insurance. You have to know everything that's ever been stuffed in the ground within half a mile of where you're working to avoid the inevitable cutting of something important -- gas, water, sewer, power, other telcom, even vacuum tube lines and subways. And then you need trenching gear to get stuff in the ground, and crews to come along behind to remediate the "environmental damage".
(Once the conduit is in the ground, it's a trivial matter to blow whatever you need through it.)
On 2017-09-01 18:38, Ricky Beam wrote:
Buried stuff requires a great deal of planning, permitting, and insurance.
Are cables in railway right of way considered "burried stuff" from the point of view of all the regulatory approvals since it is on private land (railway's) ? I take it that it is the railway which burries a new cable in its ballast (since it knows where other cables are burried, has to handle cable crossing its bridges etc)? In the specific case of Turcot in Montréal, the government was in charge of cleaning the land, removing any obstructions (such as a major sewer collector which had to be moved) etc, and even drained and compressed the ground before handing it over to CN to build its tracks. So CN got a clean slate, ready to lay tarp, ballast and tracks (and later string fibre). (ironically, that land used to belong to CN and was the Turcot rail yards).
The the USA, we have tornadoes, hurricanes, nasty wind and lightning, ice accumulation on lines, and idiot squirrels that like to eat fiber. Buried fiber over time will end up being cheaper than aerial once you factor in maintenance and repair. Add to that the additional cost of pole studies, replacement and attachments that the electric utility demands to be on their poles. When you're paying them for a pole study so that they can tell you that the pole isn't strong enough or tall enough to provide clearance, then paying them to replace the pole to make it sufficient, and then paying them monthly after that to be on the pole, just putting it in the ground starts making a lot of sense. We were affected by a fiber cut a while back caused by a truck that wiped out several electric poles. It was over 24 hours before the fiber company was even allowed access to the poles, because the electric utility wouldn't release them until they were finished. There's a lot to be said about controlling your own destiny by putting the fiber in the ground where you can work on it whenever you need to. You need insurance regardless of aerial or buried. 1/2 mile might be an exaggeration. Telcom doesn't do much trenching. Vibratory plow in open areas where there's nothing to contend with, but in urban, it's almost always directional boring. The only time we hit anything is when the other utilities fail to locate at all or fail to locate correctly. The easiest thing is to contract with a cable construction company that already has all the skills, insurance and equipment, and let them deal with it. On Fri, Sep 1, 2017 at 5:38 PM, Ricky Beam <jfbeam@gmail.com> wrote:
On Fri, 01 Sep 2017 15:52:40 -0400, Rod Beck < rod.beck@unitedcablecompany.com> wrote:
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
Aerial is simple and fast... pull the cable through a stringer, move to the next pole and repeat; when a section (about a mile) is done, it's hoisted into the air and tied to the pole. The stringers are then moved to the next mile of poles and the process repeats.
Buried stuff requires a great deal of planning, permitting, and insurance. You have to know everything that's ever been stuffed in the ground within half a mile of where you're working to avoid the inevitable cutting of something important -- gas, water, sewer, power, other telcom, even vacuum tube lines and subways. And then you need trenching gear to get stuff in the ground, and crews to come along behind to remediate the "environmental damage".
(Once the conduit is in the ground, it's a trivial matter to blow whatever you need through it.)
i'm sure theres plenty of aerial in europe. usually carried on e.g. the top messenger cable on pylons - given i've attended talks about the issues of fixing such fibre after storms in Scotland.... :) On 1 September 2017 at 20:52, Rod Beck <rod.beck@unitedcablecompany.com> wrote:
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
________________________________ From: NANOG <nanog-bounces@nanog.org> on behalf of Jared Mauch <jared@puck.nether.net> Sent: Friday, September 1, 2017 9:37 PM To: Michael Loftis Cc: Nanog@nanog.org Subject: Re: Moving fibre trunks: interruptions?
On Sep 1, 2017, at 3:32 PM, Michael Loftis <mloftis@wgops.com> wrote:
If it is in the railroad RoW they may be restricted to daylight working only. Check with your provider or OSP crew.
Yup. Railroad work is complex just because you have to coordinate with the railroad owner and they have to be onsite for all work. The cost of going underground vs aerial is also astronomical in many cases.
- Jared
Aerial's not that rare in Europe (rural areas, sometimes even close to metro). Cheers, mh Le 01/09/2017 à 21:52, Rod Beck a écrit :
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
________________________________ From: NANOG <nanog-bounces@nanog.org> on behalf of Jared Mauch <jared@puck.nether.net> Sent: Friday, September 1, 2017 9:37 PM To: Michael Loftis Cc: Nanog@nanog.org Subject: Re: Moving fibre trunks: interruptions?
On Sep 1, 2017, at 3:32 PM, Michael Loftis <mloftis@wgops.com> wrote:
If it is in the railroad RoW they may be restricted to daylight working only. Check with your provider or OSP crew.
Yup. Railroad work is complex just because you have to coordinate with the railroad owner and they have to be onsite for all work. The cost of going underground vs aerial is also astronomical in many cases.
- Jared
That depends on the country. Here in Denmark it is not possible to get rights to put up any aerial at all. The cost difference is irrelevant when you have no option but to put it in the ground. Not only is there no new aerial installations here but the old ones are taken down. Very little is left by now and in a few years it will all be gone. The municipalities want it pretty and wires in the air is ugly. One advantage however is that buried stuff usually survives storms better. Den 1. sep. 2017 21.53 skrev "Rod Beck" <rod.beck@unitedcablecompany.com>: I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
Le 02/09/2017 à 21:25, Baldur Norddahl a écrit :
That depends on the country. Here in Denmark it is not possible to get rights to put up any aerial at all. The cost difference is irrelevant when you have no option but to put it in the ground.
Not only is there no new aerial installations here but the old ones are taken down. Very little is left by now and in a few years it will all be gone. The municipalities want it pretty and wires in the air is ugly.
One advantage however is that buried stuff usually survives storms better.
Right. Here in France it (aerial running along with copper) happens even close to metropoles (like Paris). mh
Den 1. sep. 2017 21.53 skrev "Rod Beck" <rod.beck@unitedcablecompany.com>:
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
I agree as an European resident that is varies by country, but my impression is that it is a lot less. For example, fiber cuts on the European racetrack (London/Paris/Frankfurt/Amsterdam/London) seems to involve buried cable. It may just be a difference in regulatory regimes. - R. ________________________________ From: NANOG <nanog-bounces@nanog.org> on behalf of Michael Hallgren <mh@xalto.net> Sent: Saturday, September 2, 2017 9:47 PM To: nanog@nanog.org Subject: Re: Moving fibre trunks: interruptions? Le 02/09/2017 à 21:25, Baldur Norddahl a écrit :
That depends on the country. Here in Denmark it is not possible to get rights to put up any aerial at all. The cost difference is irrelevant when you have no option but to put it in the ground.
Not only is there no new aerial installations here but the old ones are taken down. Very little is left by now and in a few years it will all be gone. The municipalities want it pretty and wires in the air is ugly.
One advantage however is that buried stuff usually survives storms better.
Right. Here in France it (aerial running along with copper) happens even close to metropoles (like Paris). mh
Den 1. sep. 2017 21.53 skrev "Rod Beck" <rod.beck@unitedcablecompany.com>:
I don't think there is virtually any aerial in Europe. So given the cost difference why is virtually all fiber buried on this side of the Atlantic?
participants (12)
-
Alain Hebert -
Alan Buxey -
Baldur Norddahl -
Eric Dugas -
Jared Mauch -
Jason Baugher -
Jay Hanke -
Jean-Francois Mezei -
Michael Hallgren -
Michael Loftis -
Ricky Beam -
Rod Beck