At 10:40 AM +0100 2005-07-11, Michael.Dillon@btradianz.com wrote:
Some of the problems on the mobile networks were the result of a protocol to reserve mobile capabilities for the emergency services. The police have the authority to switch cells to emergency service and then people with specially registered SIM cards in their mobile can take priority. Presumably, some amount of capacity is also held in reserve for these people as well.
Yes, a certain amount of capacity can be placed on reserve for the holders of priority access SIMs. You only get those issued to you by the government. This can include critical emergency services personnel, selected government officials, important members of the financial services community, etc.... I don't know the specifics of how much capacity is reserved, but this sort of thing has been done on telecommunications networks for a long time. Back before cell phones existed, you could have "flash" traffic on the DDN or even the PSTN, and when placing a flash call the phone system would disconnect anyone that stood in your way of getting the connection you wanted. You had to be using special telephone equipment, or connected to a special operator with the right equipment, and you had damn well better be sure that your call was worthy of knocking anyone else off the network, but the capability was there. Even the President would normally make his calls at lower than "flash" priority. There were lower levels of priority that you could also use, but "flash" was the top one that I heard about.
I had moved the weekend before and my landline was not yet installed. Also, I live near a large hospital. I noticed that my mobile didn't function at all even late on Thursday unless I left home and travelled a kilometer or two from the hospital. Presumably, the cells in this suburban location had also been switched to emergency service.
Could be, but I'd be willing to bet it was more a matter of the cell just being overloaded. Traffic reservation for priority access SIMs is only going to take a small amount of the bandwidth available. The problem is that even normal heavy traffic can overload a cell, and what was seen during the time you're talking about was anything but "normal heavy". -- Brad Knowles, <brad@stop.mail-abuse.org> "Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See <http://www.sage.org/> for more info.