Mixing
Do layer 3 protocols use layer 2 protocols?
Clash Royale CLAN TAG#URR8PPP
up vote
2
down vote
favorite
I saw the STP on layer 2. The guy that made the tutorial says at the end :
Even though it seems that Layer 2 access layer solutions are slowly
being replaced by blazing fast Layer 3 solutions.
But when we are routing with IP on layer 3, we are then going layer 2->1 and then 1->2->.. so do we use lower layers protocols ?
Or are they used only for LAN routing ?
ip spanning-tree layer2 layer1 layer3
edited 9 mins ago
Zac67
22.4k21250
asked 8 hours ago
Romain B.
1165
add a comment |Â
up vote
2
down vote
favorite
I saw the STP on layer 2. The guy that made the tutorial says at the end :
Even though it seems that Layer 2 access layer solutions are slowly
being replaced by blazing fast Layer 3 solutions.
But when we are routing with IP on layer 3, we are then going layer 2->1 and then 1->2->.. so do we use lower layers protocols ?
Or are they used only for LAN routing ?
ip spanning-tree layer2 layer1 layer3
edited 9 mins ago
Zac67
22.4k21250
asked 8 hours ago
Romain B.
1165
Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago
add a comment |Â
up vote
2
down vote
favorite
up vote
2
down vote
favorite
I saw the STP on layer 2. The guy that made the tutorial says at the end :
Even though it seems that Layer 2 access layer solutions are slowly
being replaced by blazing fast Layer 3 solutions.
But when we are routing with IP on layer 3, we are then going layer 2->1 and then 1->2->.. so do we use lower layers protocols ?
Or are they used only for LAN routing ?
ip spanning-tree layer2 layer1 layer3
edited 9 mins ago
Zac67
22.4k21250
asked 8 hours ago
Romain B.
1165
I saw the STP on layer 2. The guy that made the tutorial says at the end :
Even though it seems that Layer 2 access layer solutions are slowly
being replaced by blazing fast Layer 3 solutions.
But when we are routing with IP on layer 3, we are then going layer 2->1 and then 1->2->.. so do we use lower layers protocols ?
Or are they used only for LAN routing ?
ip spanning-tree layer2 layer1 layer3
ip spanning-tree layer2 layer1 layer3
edited 9 mins ago
Zac67
22.4k21250
asked 8 hours ago
Romain B.
1165
edited 9 mins ago
Zac67
22.4k21250
asked 8 hours ago
Romain B.
1165
edited 9 mins ago
Zac67
22.4k21250
edited 9 mins ago
Zac67
22.4k21250
edited 9 mins ago
Zac67
22.4k21250
22.4k21250
asked 8 hours ago
Romain B.
1165
asked 8 hours ago
Romain B.
1165
asked 8 hours ago
Romain B.
1165
1165
Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago
add a comment |Â
Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago
Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago
Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago
add a comment |Â
3 Answers
3
active
oldest
votes
up vote
4
down vote
Layer 3 (mostly IP) generally relies on the underlying layer-2 network (mostly Ethernet or Wi-Fi) for delivery. Just like a layer-2 network uses layer-1 links to actually move the bits.
The difference in moving data at layer 1, 2 or 3 is the complexity of the devices. Layer-1 devices (repeaters) just copied bits - simple yet inefficient and long obsolete. Layer-2 devices (switches) intelligently forward frames and are very efficient, but layer-2 networks are limited in size. Layer-3 devices (routers) can handle networks of (theoretically) any size but their complexity initially prohibited building them in hardware. Software routers were slow and expensive. Of course, a router needs to have hardware for layers 2 and 1 as well.
Even though it seems that Layer 2 access layer solutions are slowly being replaced by blazing fast Layer 3 solutions.
This is about something different. The author describes the basic network architecture over time. Formerly, only layer-2 networks were used within a company network connected to the outside by (slow and expensive) routers. As technology advanced, routers became hardware-based and much faster. On the other hand, switches became more advanced and learned basic routing (layer-3 switching).
At the same time, networks grew much larger than they used to be, rendering the "layer 2 throughout" design obsolete - layer-2 networks only scale in a limited way.
With performance up and cost down, it became common design to use routers and layer-3 switch in the core. Today, the layer-3 approach has grown outside from the core into the aggregation layer, enabling even larger networks. The next step is to also use routing instead of switching in the access layer where the clients are connected.
answered 8 hours ago
Zac67
22.4k21250
add a comment |Â
up vote
2
down vote
It used to be, "Switch where you can, route where you must." That has been turned on its head. Of course, an interface, even on a layer-3 router, uses both layer-1 and layer-2 protocols. I think the idea is that the current best practices are moving toward routing all the way to the access switch. Within the access switch, you are still layer-2, but the access switches connect to the distribution via layer-3 connections and routing, and access switches do not connect to each other.
That means that a VLAN exists only on the single access switch, You can have multiple VLANs on a single access switch, but those VLANs do not extend to any other access switches. This will almost completely remove any STP or other layer-2 problems, e.g. broadcast storms, that can bring an entire site to its knees. We live in a layer-3 world, and it is now rare to have an application that needs the same VLAN across all the hosts. We route across the Internet, so why not route in your own network?
The reason it has been changing is that we now have a lot of layer-3 switches used as access switches that can route to the distribution.
answered 8 hours ago
Ron Maupin♦
58.8k1058106
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
 |Â
show 3 more comments
up vote
2
down vote
The quote you quoted is simply misleading. All modern network devices transmit data at wire speed, so they're all "blazing fast." Whether it's layer 2 or 3 makes no difference in data rates.
A host will create data, and then encapsulate it in a lower level protocol data unit. So TCP gets encapsulated in IP, which gets encapsulated in 802.11, etc. It's all 1's and 0's when it leaves the computer. The receiving host reverses the process and de-encapsulates the data as it moves up the protocol software stack.
answered 8 hours ago
Ron Trunk
32.3k22868
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
 |Â
show 1 more comment
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
4
down vote
Layer 3 (mostly IP) generally relies on the underlying layer-2 network (mostly Ethernet or Wi-Fi) for delivery. Just like a layer-2 network uses layer-1 links to actually move the bits.
The difference in moving data at layer 1, 2 or 3 is the complexity of the devices. Layer-1 devices (repeaters) just copied bits - simple yet inefficient and long obsolete. Layer-2 devices (switches) intelligently forward frames and are very efficient, but layer-2 networks are limited in size. Layer-3 devices (routers) can handle networks of (theoretically) any size but their complexity initially prohibited building them in hardware. Software routers were slow and expensive. Of course, a router needs to have hardware for layers 2 and 1 as well.
Even though it seems that Layer 2 access layer solutions are slowly being replaced by blazing fast Layer 3 solutions.
This is about something different. The author describes the basic network architecture over time. Formerly, only layer-2 networks were used within a company network connected to the outside by (slow and expensive) routers. As technology advanced, routers became hardware-based and much faster. On the other hand, switches became more advanced and learned basic routing (layer-3 switching).
At the same time, networks grew much larger than they used to be, rendering the "layer 2 throughout" design obsolete - layer-2 networks only scale in a limited way.
With performance up and cost down, it became common design to use routers and layer-3 switch in the core. Today, the layer-3 approach has grown outside from the core into the aggregation layer, enabling even larger networks. The next step is to also use routing instead of switching in the access layer where the clients are connected.
answered 8 hours ago
Zac67
22.4k21250
add a comment |Â
up vote
4
down vote
Layer 3 (mostly IP) generally relies on the underlying layer-2 network (mostly Ethernet or Wi-Fi) for delivery. Just like a layer-2 network uses layer-1 links to actually move the bits.
The difference in moving data at layer 1, 2 or 3 is the complexity of the devices. Layer-1 devices (repeaters) just copied bits - simple yet inefficient and long obsolete. Layer-2 devices (switches) intelligently forward frames and are very efficient, but layer-2 networks are limited in size. Layer-3 devices (routers) can handle networks of (theoretically) any size but their complexity initially prohibited building them in hardware. Software routers were slow and expensive. Of course, a router needs to have hardware for layers 2 and 1 as well.
Even though it seems that Layer 2 access layer solutions are slowly being replaced by blazing fast Layer 3 solutions.
This is about something different. The author describes the basic network architecture over time. Formerly, only layer-2 networks were used within a company network connected to the outside by (slow and expensive) routers. As technology advanced, routers became hardware-based and much faster. On the other hand, switches became more advanced and learned basic routing (layer-3 switching).
At the same time, networks grew much larger than they used to be, rendering the "layer 2 throughout" design obsolete - layer-2 networks only scale in a limited way.
With performance up and cost down, it became common design to use routers and layer-3 switch in the core. Today, the layer-3 approach has grown outside from the core into the aggregation layer, enabling even larger networks. The next step is to also use routing instead of switching in the access layer where the clients are connected.
answered 8 hours ago
Zac67
22.4k21250
add a comment |Â
up vote
4
down vote
up vote
4
down vote
Layer 3 (mostly IP) generally relies on the underlying layer-2 network (mostly Ethernet or Wi-Fi) for delivery. Just like a layer-2 network uses layer-1 links to actually move the bits.
The difference in moving data at layer 1, 2 or 3 is the complexity of the devices. Layer-1 devices (repeaters) just copied bits - simple yet inefficient and long obsolete. Layer-2 devices (switches) intelligently forward frames and are very efficient, but layer-2 networks are limited in size. Layer-3 devices (routers) can handle networks of (theoretically) any size but their complexity initially prohibited building them in hardware. Software routers were slow and expensive. Of course, a router needs to have hardware for layers 2 and 1 as well.
Even though it seems that Layer 2 access layer solutions are slowly being replaced by blazing fast Layer 3 solutions.
This is about something different. The author describes the basic network architecture over time. Formerly, only layer-2 networks were used within a company network connected to the outside by (slow and expensive) routers. As technology advanced, routers became hardware-based and much faster. On the other hand, switches became more advanced and learned basic routing (layer-3 switching).
At the same time, networks grew much larger than they used to be, rendering the "layer 2 throughout" design obsolete - layer-2 networks only scale in a limited way.
With performance up and cost down, it became common design to use routers and layer-3 switch in the core. Today, the layer-3 approach has grown outside from the core into the aggregation layer, enabling even larger networks. The next step is to also use routing instead of switching in the access layer where the clients are connected.
answered 8 hours ago
Zac67
22.4k21250
Layer 3 (mostly IP) generally relies on the underlying layer-2 network (mostly Ethernet or Wi-Fi) for delivery. Just like a layer-2 network uses layer-1 links to actually move the bits.
The difference in moving data at layer 1, 2 or 3 is the complexity of the devices. Layer-1 devices (repeaters) just copied bits - simple yet inefficient and long obsolete. Layer-2 devices (switches) intelligently forward frames and are very efficient, but layer-2 networks are limited in size. Layer-3 devices (routers) can handle networks of (theoretically) any size but their complexity initially prohibited building them in hardware. Software routers were slow and expensive. Of course, a router needs to have hardware for layers 2 and 1 as well.
Even though it seems that Layer 2 access layer solutions are slowly being replaced by blazing fast Layer 3 solutions.
This is about something different. The author describes the basic network architecture over time. Formerly, only layer-2 networks were used within a company network connected to the outside by (slow and expensive) routers. As technology advanced, routers became hardware-based and much faster. On the other hand, switches became more advanced and learned basic routing (layer-3 switching).
At the same time, networks grew much larger than they used to be, rendering the "layer 2 throughout" design obsolete - layer-2 networks only scale in a limited way.
With performance up and cost down, it became common design to use routers and layer-3 switch in the core. Today, the layer-3 approach has grown outside from the core into the aggregation layer, enabling even larger networks. The next step is to also use routing instead of switching in the access layer where the clients are connected.
answered 8 hours ago
Zac67
22.4k21250
edited 8 hours ago
answered 8 hours ago
Zac67
22.4k21250
answered 8 hours ago
Zac67
22.4k21250
answered 8 hours ago
Zac67
22.4k21250
22.4k21250
add a comment |Â
add a comment |Â
up vote
2
down vote
It used to be, "Switch where you can, route where you must." That has been turned on its head. Of course, an interface, even on a layer-3 router, uses both layer-1 and layer-2 protocols. I think the idea is that the current best practices are moving toward routing all the way to the access switch. Within the access switch, you are still layer-2, but the access switches connect to the distribution via layer-3 connections and routing, and access switches do not connect to each other.
That means that a VLAN exists only on the single access switch, You can have multiple VLANs on a single access switch, but those VLANs do not extend to any other access switches. This will almost completely remove any STP or other layer-2 problems, e.g. broadcast storms, that can bring an entire site to its knees. We live in a layer-3 world, and it is now rare to have an application that needs the same VLAN across all the hosts. We route across the Internet, so why not route in your own network?
The reason it has been changing is that we now have a lot of layer-3 switches used as access switches that can route to the distribution.
answered 8 hours ago
Ron Maupin♦
58.8k1058106
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
 |Â
show 3 more comments
up vote
2
down vote
It used to be, "Switch where you can, route where you must." That has been turned on its head. Of course, an interface, even on a layer-3 router, uses both layer-1 and layer-2 protocols. I think the idea is that the current best practices are moving toward routing all the way to the access switch. Within the access switch, you are still layer-2, but the access switches connect to the distribution via layer-3 connections and routing, and access switches do not connect to each other.
That means that a VLAN exists only on the single access switch, You can have multiple VLANs on a single access switch, but those VLANs do not extend to any other access switches. This will almost completely remove any STP or other layer-2 problems, e.g. broadcast storms, that can bring an entire site to its knees. We live in a layer-3 world, and it is now rare to have an application that needs the same VLAN across all the hosts. We route across the Internet, so why not route in your own network?
The reason it has been changing is that we now have a lot of layer-3 switches used as access switches that can route to the distribution.
answered 8 hours ago
Ron Maupin♦
58.8k1058106
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
 |Â
show 3 more comments
up vote
2
down vote
up vote
2
down vote
It used to be, "Switch where you can, route where you must." That has been turned on its head. Of course, an interface, even on a layer-3 router, uses both layer-1 and layer-2 protocols. I think the idea is that the current best practices are moving toward routing all the way to the access switch. Within the access switch, you are still layer-2, but the access switches connect to the distribution via layer-3 connections and routing, and access switches do not connect to each other.
That means that a VLAN exists only on the single access switch, You can have multiple VLANs on a single access switch, but those VLANs do not extend to any other access switches. This will almost completely remove any STP or other layer-2 problems, e.g. broadcast storms, that can bring an entire site to its knees. We live in a layer-3 world, and it is now rare to have an application that needs the same VLAN across all the hosts. We route across the Internet, so why not route in your own network?
The reason it has been changing is that we now have a lot of layer-3 switches used as access switches that can route to the distribution.
answered 8 hours ago
Ron Maupin♦
58.8k1058106
It used to be, "Switch where you can, route where you must." That has been turned on its head. Of course, an interface, even on a layer-3 router, uses both layer-1 and layer-2 protocols. I think the idea is that the current best practices are moving toward routing all the way to the access switch. Within the access switch, you are still layer-2, but the access switches connect to the distribution via layer-3 connections and routing, and access switches do not connect to each other.
That means that a VLAN exists only on the single access switch, You can have multiple VLANs on a single access switch, but those VLANs do not extend to any other access switches. This will almost completely remove any STP or other layer-2 problems, e.g. broadcast storms, that can bring an entire site to its knees. We live in a layer-3 world, and it is now rare to have an application that needs the same VLAN across all the hosts. We route across the Internet, so why not route in your own network?
The reason it has been changing is that we now have a lot of layer-3 switches used as access switches that can route to the distribution.
answered 8 hours ago
Ron Maupin♦
58.8k1058106
answered 8 hours ago
Ron Maupin♦
58.8k1058106
answered 8 hours ago
Ron Maupin♦
58.8k1058106
answered 8 hours ago
Ron Maupin♦
58.8k1058106
58.8k1058106
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
 |Â
show 3 more comments
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
Do we still use layer 2 protocols in LAN ?
– Romain B.
8 hours ago
1
1
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
Yes we do, Ethernet and 802.11 (Wi-Fi) are layer 2 protocols.
– Ron Trunk
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
So when I'm connected on ethernet and I'm sending a packet, it's routed using layer 2 protocol until it reaches the router and then it uses IP routing ?
– Romain B.
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
Layer-2 doesn't route, it bridges frames. Layer-3 routes packets.
– Ron Maupin♦
8 hours ago
1
1
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
Yes, bridges bridge frames using a table, or flooding of the frame if the destination is not in the table. The frames do not include a bridge ID. That is part of STP, and it is in the BPDUs sent by bridges to each other in order to determine a loop-free path. Bridges only look at the frame to forward the frames, but routers strip off the frame to get to the packet.
– Ron Maupin♦
8 hours ago
 |Â
show 3 more comments
up vote
2
down vote
The quote you quoted is simply misleading. All modern network devices transmit data at wire speed, so they're all "blazing fast." Whether it's layer 2 or 3 makes no difference in data rates.
A host will create data, and then encapsulate it in a lower level protocol data unit. So TCP gets encapsulated in IP, which gets encapsulated in 802.11, etc. It's all 1's and 0's when it leaves the computer. The receiving host reverses the process and de-encapsulates the data as it moves up the protocol software stack.
answered 8 hours ago
Ron Trunk
32.3k22868
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
 |Â
show 1 more comment
up vote
2
down vote
The quote you quoted is simply misleading. All modern network devices transmit data at wire speed, so they're all "blazing fast." Whether it's layer 2 or 3 makes no difference in data rates.
A host will create data, and then encapsulate it in a lower level protocol data unit. So TCP gets encapsulated in IP, which gets encapsulated in 802.11, etc. It's all 1's and 0's when it leaves the computer. The receiving host reverses the process and de-encapsulates the data as it moves up the protocol software stack.
answered 8 hours ago
Ron Trunk
32.3k22868
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
 |Â
show 1 more comment
up vote
2
down vote
up vote
2
down vote
The quote you quoted is simply misleading. All modern network devices transmit data at wire speed, so they're all "blazing fast." Whether it's layer 2 or 3 makes no difference in data rates.
A host will create data, and then encapsulate it in a lower level protocol data unit. So TCP gets encapsulated in IP, which gets encapsulated in 802.11, etc. It's all 1's and 0's when it leaves the computer. The receiving host reverses the process and de-encapsulates the data as it moves up the protocol software stack.
answered 8 hours ago
Ron Trunk
32.3k22868
The quote you quoted is simply misleading. All modern network devices transmit data at wire speed, so they're all "blazing fast." Whether it's layer 2 or 3 makes no difference in data rates.
A host will create data, and then encapsulate it in a lower level protocol data unit. So TCP gets encapsulated in IP, which gets encapsulated in 802.11, etc. It's all 1's and 0's when it leaves the computer. The receiving host reverses the process and de-encapsulates the data as it moves up the protocol software stack.
answered 8 hours ago
Ron Trunk
32.3k22868
answered 8 hours ago
Ron Trunk
32.3k22868
answered 8 hours ago
Ron Trunk
32.3k22868
answered 8 hours ago
Ron Trunk
32.3k22868
32.3k22868
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
 |Â
show 1 more comment
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Yes, I think he meant how long it takes to get a spanning tree using the protocol
– Romain B.
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
Rapid Spanning Tree protocol (802.3w) is a significant improvement on convergence time.
– Ron Trunk
8 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
It most likely isn't misleading in the context in which it appeared, which I expect is about replacing layer 2 routing algorithms (which are simplistic) with layer 3 routing algorithms (which are more advanced). A layer 2 network is one with mostly switches and a layer 3 network is one with mostly routers - of course there is a very simple layer-2 network between each pair of routers, but if you're not doing any layer 2 switching then it's irrelevant.
– immibis
3 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@immibis There is no routing at layer 2 because routing is a layer 3 function.
– Ron Trunk
2 hours ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
@RonTrunk Fine then, layer 2 and layer 3 forwarding algorithms. Or if that doesn't work either, layer 2 and layer 3 algorithms to determine where to send a packet.
– immibis
1 hour ago
 |Â
show 1 more comment
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Layer 3 delivery relies on layer 2 delivery, but layer 2 "routing" and layer 3 routing are completely different.
– immibis
3 hours ago