Ok, you're not interested in the event that could cause the shutdown but I'm going to assume that local infrastructure has remained intact but anything part of long distance dedicated packet based network has been zapped by aliens or something.

I'm going to exclude networks not usually used for packet data despite the fact that IP over avian carriers is a thing that can be done. The aliens have not shot down all carrier pigeons.

Old-style non-packet based networks like old phone connections are also still alive even though people can technically send packet data over them.

I'm assuming that every running non-leaf node in any primarily packet based communication networks has burned and any long cable has been broken at some random point along it's length.

Seconds= every on-call network engineer on the planet is woken as contact is lost with their networks except those who relied too heavily on other networks for their wakeup call.

Minutes= people start noticing that they can't make phone calls, 911 calls are no longer a thing except in areas with really old phone networks. A few people start to get a little annoyed because they have no signal, the network engineers are currently leaping into their cars or trying to contact others. A large portion of the rest of the worlds on-call tech staff are being woken, some by banging at their door. Some systems like nuclear power plants are likely going into failsafe mode and shutting down or being shut down by their staff for safety sake since they've lost contact with other nodes in the grid.

Hours= it's really starting to hit the fan. The dying has started in small numbers, operations being performed remotely are screwed up. Local ham radio enthusiasts are being turned out of bed by police/local officials and apart from emergency radio broadcasts the entire spectrum is being commandeered for emergency use, high priority communication is starting to be pushed over quickly jury rigged radio links, some of it voice, some of it packet based. Most of the world still doesn't know anything has gone seriously wrong. AM radios start issuing announcements and warnings. Military is on highest alert assuming a surprise attack, fortunately red-phone style systems are likely not packet based. India and Pakistan nuke each other anyway.

Days= stock in companies which produce networking gear is heading for pluto, or it would be if many of the exchanges weren't legally not allowed to operate since many mandated communication links are dead. Any company which has the facilities to produce networking gear or cables is doing so as fast as they can to cash in. Lots of old hardware is being pulled out of storage. There's probably a lot of people scared. many areas are blacked out as many of the power plants can't get supplies or can't be safely run or coordinated.

Weeks= looting, rioting, many shipping networks have been screwed up so there's a shortage of almost everything while food rots in the fields due to breakdowns in communication but the networking engineers of the world have yet to sleep and have all been pulling 72 hour shifts. high priority, low bandwidth links have been restored within most first world nations between cities but ocean cables are still down. Lots of local infrastructure is screwed. Ditto bureaucracy.

Most network dependent industry pretty much collapses but there's lots and lots of jobs running fiber/cable and installing switches.

Ok, you're not interested in the event that could cause the shutdown but I'm going to assume that local infrastructure has remained intact but anything part of long distance dedicated packet based network has been zapped by aliens or something.

I'm going to exclude networks not usually used for packet data despite the fact that IP over avian carriers is a thing that can be done. The aliens have not shot down all carrier pigeons.

Old-style non-packet based networks like old phone connections are also still alive even though people can technically send packet data over them.

I'm assuming that every running non-leaf node in any primarily packet based communication networks has burned and any long cable has been broken at some random point along it's length.

Seconds= every on-call network engineer on the planet is woken as contact is lost with their networks except those who relied too heavily on other networks for their wakeup call.

Minutes= people start noticing that they can't make phone calls, 911 calls are no longer a thing except in areas with really old phone networks. A few people start to get a little annoyed because they have no signal, the network engineers are currently leaping into their cars or trying to contact others. A large portion of the rest of the worlds on-call tech staff are being woken, some by banging at their door. Some systems like nuclear power plants are likely going into failsafe mode and shutting down or being shut down by their staff for safety sake since they've lost contact with other nodes in the grid.

Hours= it's really starting to hit the fan. The dying has started in small numbers, operations being performed remotely are screwed up. Local ham radio enthusiasts are being turned out of bed by police/local officials and apart from emergency radio broadcasts the entire spectrum is being commandeered for emergency use, high priority communication is starting to be pushed over quickly jury rigged radio links, some of it voice, some of it packet based. Most of the world still doesn't know anything has gone seriously wrong. AM radios start issuing announcements and warnings. Military is on highest alert assuming a surprise attack, fortunately red-phone style systems are likely not packet based. India and Pakistan nuke each other anyway.

Days= stock in companies which produce networking gear is heading for pluto, or it would be if many of the exchanges weren't legally not allowed to operate since many mandated communication links are dead. Any company which has the facilities to produce networking gear or cables is doing so as fast as they can to cash in. Lots of old hardware is being pulled out of storage. There's probably a lot of people scared. many areas are blacked out as many of the power plants can't get supplies or can't be safely run or coordinated.

Weeks= looting, rioting, many shipping networks have been screwed up so there's a shortage of almost everything while food rots in the fields due to breakdowns in communication but the networking engineers of the world have yet to sleep and have all been pulling 72 hour shifts. high priority, low bandwidth links have been restored within most first world nations between cities but ocean cables are still down. Lots of local infrastructure is screwed. Ditto bureaucracy.

Most network dependent industry pretty much collapses but there's lots and lots of jobs running fiber/cable and installing switches.

Ok, you're not interested in the event that could cause the shutdown but I'm going to assume that local infrastructure has remained intact but anything part of long distance dedicated packet based network has been zapped by aliens or something.

I'm going to exclude networks not usually used for packet data despite the fact that IP over avian carriers is a thing that can be done. The aliens have not shot down all carrier pigeons.

Old-style non-packet based networks like old phone connections are also still alive even though people can technically send packet data over them.

seconds= every on-call network engineer on the planet is woken as contact is lost with their networks except those who relied too heavily on other networks for their wakeup call.

I'm assuming that every running non-leaf node in any primarily packet based communication networks has burned and any long cable has been broken at some random point along it's length.

minutes= people start noticing that they can't make phone calls, 911 calls are no longer a thing except in areas with really old phone networks. A few people start to get a little annoyed because they have no signal, the network engineers are currently leaping into their cars or trying to contact others. A large portion of the rest of the worlds on-call tech staff are being woken, some by banging at their door. Some systems like nuclear power plants are likely going into failsafe mode and shutting down or being shut down by their staff for safety sake since they've lost contact with other nodes in the grid.

hours= it's really starting to hit the fan. The dying has started in small numbers, operations being performed remotely are screwed up. Local ham radio enthusiasts are being turned out of bed by police/local officials and apart from emergency radio broadcasts the entire spectrum is being commandeered for emergency use, high priority communication is starting to be pushed over quickly jury rigged radio links, some of it voice, some of it packet based. Most of the world still doesn't know anything has gone seriously wrong. AM radios start issuing announcements and warnings. Military is on highest alert assuming a surprise attack, fortunately red-phone style systems are likely not packet based. India and Pakistan nuke each other anyway.

days= stock in companies which produce networking gear is heading for pluto, or it would be if many of the exchanges weren't legally not allowed to operate since many mandated communication links are dead. Any company which has the facilities to produce networking gear or cables is doing so as fast as they can to cash in. Lots of old hardware is being pulled out of storage. There's probably a lot of people scared. many areas are blacked out as many of the power plants can't get supplies or can't be safely run or coordinated.

weeks= looting, rioting, many shipping networks have been screwed up so there's a shortage of almost everything while food rots in the fields due to breakdowns in communication but the networking engineers of the world have yet to sleep and have all been pulling 72 hour shifts. high priority, low bandwidth links have been restored within most first world nations between cities but ocean cables are still down. Lots of local infrastructure is screwed. Ditto bureaucracy.

Every most network dependent industry pretty much collapses but there's lots and lots of jobs running fiber/cable and installing switches.

Ok, you're not interested in the event that could cause the shutdown but I'm going to assume that local infrastructure has remained intact but anything part of long distance dedicated packet based network has been zapped by aliens or something.

I'm going to exclude networks not usually used for packet data despite the fact that IP over avian carriers is a thing that can be done. The aliens have not shot down all carrier pigeons.

Old-style non-packet based networks like old phone connections are also still alive even though people can technically send packet data over them.

I'm assuming that every running non-leaf node in any primarily packet based communication networks has burned and any long cable has been broken at some random point along it's length.

Seconds= every on-call network engineer on the planet is woken as contact is lost with their networks except those who relied too heavily on other networks for their wakeup call.

Minutes= people start noticing that they can't make phone calls, 911 calls are no longer a thing except in areas with really old phone networks. A few people start to get a little annoyed because they have no signal, the network engineers are currently leaping into their cars or trying to contact others. A large portion of the rest of the worlds on-call tech staff are being woken, some by banging at their door. Some systems like nuclear power plants are likely going into failsafe mode and shutting down or being shut down by their staff for safety sake since they've lost contact with other nodes in the grid.

Hours= it's really starting to hit the fan. The dying has started in small numbers, operations being performed remotely are screwed up. Local ham radio enthusiasts are being turned out of bed by police/local officials and apart from emergency radio broadcasts the entire spectrum is being commandeered for emergency use, high priority communication is starting to be pushed over quickly jury rigged radio links, some of it voice, some of it packet based. Most of the world still doesn't know anything has gone seriously wrong. AM radios start issuing announcements and warnings. Military is on highest alert assuming a surprise attack, fortunately red-phone style systems are likely not packet based. India and Pakistan nuke each other anyway.

Days= stock in companies which produce networking gear is heading for pluto, or it would be if many of the exchanges weren't legally not allowed to operate since many mandated communication links are dead. Any company which has the facilities to produce networking gear or cables is doing so as fast as they can to cash in. Lots of old hardware is being pulled out of storage. There's probably a lot of people scared. many areas are blacked out as many of the power plants can't get supplies or can't be safely run or coordinated.

Weeks= looting, rioting, many shipping networks have been screwed up so there's a shortage of almost everything while food rots in the fields due to breakdowns in communication but the networking engineers of the world have yet to sleep and have all been pulling 72 hour shifts. high priority, low bandwidth links have been restored within most first world nations between cities but ocean cables are still down. Lots of local infrastructure is screwed. Ditto bureaucracy.

Most network dependent industry pretty much collapses but there's lots and lots of jobs running fiber/cable and installing switches.