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4 votes

Why is MPLS label added between layer 2 header and layer 3 header of OSI model and not between headers of layer 3 and 4 of OSI model?

MPLS is a layer-2 protocol. However, no layer-1 carries MPLS directly, so it gets tacked on to various other layer-2 protocols. (hence "layer-2.5") Adding it after a layer-3 header would ...
Ricky's user avatar
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3 votes

Tagged frames onto untagged (access) port!

This question has been asked at least a dozen times. We can only guess why the spec says what it says -- no one here wrote it. Despite what the spec says, no one does that -- "ingress filtering" is ...
Ricky's user avatar
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2 votes

Broadcasting in L2 Switch

A broadcast frame is forwarded to all switch ports but the one it was received from. When several switches are connected to each other the broadcast will eventually reach all ports in this broadcast ...
Zac67's user avatar
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2 votes

Connecting two switches with an access mode port

You don't mention brand of the switch, any management software, or any configuration (in particular how that interface was previously configured), so I can only answer generically. Most default ...
YLearn's user avatar
  • 27.4k
2 votes

Why Switching Modes and when to use one of the other?

This is a lot more complex than just a software-selectable forwarding option - and is true not only for Cisco but most other vendors. First of all - store-and-forward vs cut-through generally isn't ...
rnxrx's user avatar
  • 6,124
2 votes
Accepted

How many PoE ports can I use on a switch?

It rather depends on what is real. 24V 6.5W is not 24V 0.5 A - but I think the latter number is just what the default (passive) POE power brick is, and they are oversized somewhat by default. 24V 0....
Ecnerwal's user avatar
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2 votes

How many PoE ports can I use on a switch?

I don't know the exact model you are using, but the specs I read say 48V @.5A. That's 24 watts (and is more inline with similar APs) 23 ports @ 24W = 552 Watts. So, no, you can't power all the ...
Ron Trunk's user avatar
  • 67.7k
2 votes

Inter-VLAN Routing

Configure each VLAN with "no shutdown." Make sure that the VLANs are active. "Conf t" and the type "vlan 2" and see if that brings the VLAN up. Do this with the rest of the VLANs. Make sure that each ...
Jared Elliott's user avatar
2 votes

dhcp client not receving the ip address using two switches

On switch 2, the client ports are on VLAN 100 and 200 (not 10 and 20). EDITED to include Marc Luethi's comment: On ESW2, the switchports where R1, R2, R3 are connected are without spanning-tree ...
Ron Trunk's user avatar
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2 votes
Accepted

Non [R]STP switches in LAN ring topology

If you plan to create a ring of switches, all those switches need to support RSTP or MSTP. That is, unless all the unmanaged switches completely ignore IEEE 802.1D and actually forward the RSTP BPDUs -...
Zac67's user avatar
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2 votes

What are the Major Differences between Juniper EX4200 vs Juniper EX4300?

EX4300s have four QSFP+ ports (rear panel) which may be used for stacking or as 40GbE. They also don't require an uplink module (EX-UM-xxx) and therefore have four SFP+ 1/10G ports (front panel) in ...
Jeff Wheeler's user avatar
  • 5,502
2 votes
Accepted

What are the Major Differences between Juniper EX4200 vs Juniper EX4300?

If you're looking at purchasing new hardware, EX4300s are generally recommended. It's not that there's anything wrong with the EX4200, it's simply that the EX4300 is the next generation with new ...
Jordan Head's user avatar
  • 7,119
2 votes

How to reset a Default username and password of Allied Telesis AT9000/28 switch using CLI?

I would defy the purpose - securing management access - if you could reset the credentials via console. As it seems, AT has made no provisions to reset the password by physical reset switch either. ...
Zac67's user avatar
  • 85.5k
2 votes
Accepted

Message switching vs packet switching with respect to congestion traffic

This seems to assume that queues can have limited number of packets (true enough), but unlimited packet size (not true). The idea that a large message packet size uses fewer places in the queue is ...
Ron Maupin's user avatar
  • 99.9k
1 vote
Accepted

cut-through vs store-and-forward switching

We assume that [...] the delay inside the switches is 0. [...] We should have an end-to-end delay equal to 1 x transmission time according to the same reference. The "delay inside the switches&...
Zac67's user avatar
  • 85.5k
1 vote

Can anyone please explain L3 SVI configuration ,What is SVI and Where do we use it?

On Cisco devices, SVI's are configured just like a physical interface. They are named for the vlan they're attached to. For example, the SVI for Vlan 10 is named interface vlan10. To assign an IPv4 ...
Ron Trunk's user avatar
  • 67.7k
1 vote

Can anyone please explain L3 SVI configuration ,What is SVI and Where do we use it?

An SVI is a Switched Virtual Interface. It is an interface for the VLAN itself on the switch. It can be a layer-3 interface (IP addressing) to allow the switch itself to participate in the VLAN. A ...
Ron Maupin's user avatar
  • 99.9k
1 vote

Sending tagged traffic to untagged port?

An access port that receives tagged traffic will drop the tagged frames.
Ron Trunk's user avatar
  • 67.7k
1 vote

Inter-VLAN Routing

You still need to configure the VLAN 3 SVI on the L3 switch. You also need to set trunk mode and encapsulation on Fa0/24 of all three L2 switches.
Jacktose's user avatar
  • 476
1 vote

About the switchport mode

Specifically concerning negotiate or nonegotiate ... By default, the negotiation port setting is on, that is , the ability to negotiate a trunk port (if not a trunk the port becomes an access port.) ...
Fletch's user avatar
  • 43
1 vote

Can't establish the connection for switch

Your problem is that the VTP passwords don't match. On the non-working switch: MD5 digest : 0xB9 0x07 0xEE 0xE3 0x27 0xEC 0xF7 0x33 0x98 ...
Ron Maupin's user avatar
  • 99.9k

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