Questions tagged [layer3]
For questions about the OSI layer-3 (network layer).
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How to assign a static IP to a Cisco Layer 3 switch in order to connect using SSH?
The steps of this manual have been executed in order to configure SSH.
Once SSH has been configured, how to access the switch from a computer using SSH?
The following steps have been executed in ...
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3
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When are MAC addresses used instead of IP addresses in the OSI model?
Okay, so I'm studying for the Network+ exam, and I've gone over the OSI model about a million times, and I understand most of it fairly well, and my studies are coming along fine. However, there is ...
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Layer 3 Switching in Packet Tracer not working
I am studying for ICND1 through CBTNuggets,
I recently watched videos on how to interact between different vlans using separate interfaces, sub-interfaces and Layer 3 Switching.
The first two worked ...
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When is a layer 3 switch more appropriate than a router in a branch office?
It seems that as time passes, vendors have added almost all the features of a router to a layer 3 switch.
For branch office deployments, how do other people who design networks choose between ...
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Difference between router leg and static routes
I am looking a L2/L3 switch spec. which says it supports 256 Router Legs and maximum of 32 Static routes.
Can somebody explain with an example, what is the difference between router leg and static ...
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Connect Multiple VLANs which reside on same L3 Switch
Introduction
The steps described in this manual have been applied in order to enable the connection between multiple VLANs which reside on the same switch.
Two VLANs have been configured.
VLAN 1:
...
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What is the difference between MSS and MTU?
I'm confused as to the difference between maximum segment size and a maximum transmission unit.
Can someone please explain in relation to layers 2 and 3?
If I had a packet of 800 bytes in the ...
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Routing Between Cisco 4507R+E Layer 3 Switch & UTM Firewall Fortigate
Please Help me.
I have a Cisco Catalyst 4507R+E and UTM Firewall Fortigate and I Created VLANS on Catalyst and the main VLAN port Which Play IP Route between All VLANs can not connectet to the UTM ...
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How does BGP work over TCP?
As far as I know we are using routing protocols to achieve Layer 3 connectivity, I am confused with the fact that BGP works over TCP which is L4. How can L4/TCP be established without prior L3 ...
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What, exactly, is required to make Airplay work across VLANs? [closed]
It seems like AirPlay works out-of-the-box, vaguely speaking, only within a LAN. It's not clear to me exactly why, but it looks like at least discovery relies on broadcasts. Wikipedia states that ...
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Routing throughput of an L3 switch
The Cisco SG300-10 says its forwarding rate is 14.88Mpps with 64 byte packets. I estimated this to be ~ 7 Gb/s.
Does this mean that up to 7 computers can transfer data across VLANs at full 1 Gb/s ...
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Why are there checksums for different OSI layers?
Can anyone clarify the question "why we need checksum in both layer-2 and layer-3 of OSI layer", Layer-2 would encapsulate the rest of OSI layers into a single unit.
If Layer-2 has a checksum, ...
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'interface vlanX' or 'interface loopbackX'
VLANs are a layer 2 concept. We can all agree on that but why, then, do we use the 'interface vlanX' to allow routing on a switch. If we want to setup a default gateway for VLAN X on a Layer 3 switch ...
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Routing of 2 Gateways via a Layer 2 Switch
Please refer to the network diagram below, it is a very simplified version of an actual network installation.
The Router has 3 Vlans, OSPF has been configured and all the 3 vlans have been added to ...
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Is Layer 3 web auth with Layer 2 PSK more secure?
I have configured a Cisco WLC to authenticate users using External Web Authentication at Layer 3. Are client wifi connections more resilient against eavesdroppers with a pre-shared key at Layer 2 ...
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Cisco ASA Routing Issue
I am working on a lab right now and am having some issues with ASA routing.
Here is the current network topology:
Currently if I login to the console on the ASA or Router I can get outside to the ...
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What layer of the OSI model does NAT work?
Simple question and the answer is layer 3 of course, but can we say that PAT is working on layer 4 also because it deals with port numbers which is a layer 4 function?
Or is it only a layer 3 ...
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Layer 3 network, multiple internet connections
I'm using a Procurve 5406zl (J8697A) layer 3 switch with multiple vlans:
VLANs:
v10 Main Network 10.1.4.1
v12 Wireless 10.1.8.1
v13 Restricted Wireless 10.0.0.1
v14 Tech 192.168.7.1
v50 Internet 192....
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