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12 votes
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Does bridging add delay?

Hi and welcome to Network Engineering. As for "delay" vs "latency": The terms are not always used consistently. Some hints may be found here. I think generally, the term latency is used when ...
Marc 'netztier' Luethi's user avatar
11 votes
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Difference between Linux Bridge and Open vSwitch

Open vSwitch has a section on that in their FAQ: Q: Why would I use Open vSwitch instead of the Linux bridge? A: Open vSwitch is specially designed to make it easier to manage VM network ...
RobinG's user avatar
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9 votes
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Why routers change mac address of frames (and bridge not)?

Routers do not change the MAC address, they completely strip off the layer-2 frame, losing any layer-2 information, e.g. MAC addressing. A router then routes the layer-3 packet that was encapsulated ...
Ron Maupin's user avatar
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8 votes

Does bridging add delay?

Yes, a bridge / switch adds some delay to a frame - in the order of 1 to 20 µs. For switches you usually speak of latency - the delay between receiving a frame and forwarding it out another port. A ...
Zac67's user avatar
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7 votes

What is a VLAN (really)?

A VLAN is a layer 2 construct which separates devices into separate broadcast domains. A VLAN is a group of devices on one or more LANs that are configured to communicate as if they were attached to ...
Maverick's user avatar
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6 votes

Why does STP choose the lowest bridge ID as the root bridge?

Why should we choose the switch which has "the lowest" bridge ID to be the root bridge,not "the highest" ? Because that is the standard, and it has been for decades, so it is not ...
Ron Maupin's user avatar
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5 votes
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How transparent bridging Wi-Fi with Ethernet works?

You seem to be confusing the different network layers. Routers route packets at layer-3, using the layer-3, e.g. IP, addresses, but bridging happens at layer-2, using layer-2, e.g. MAC, addresses. ...
Ron Maupin's user avatar
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5 votes
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Bridging networks without NAT: how it's done?

You seem to be confusing layer-2 and layer-3. Bridging is not routing. Bridging has nothing to do with layer-3 addresses, and routing removes the layer-2 addresses. Routers route packets, and bridges ...
Ron Maupin's user avatar
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5 votes

What is a VLAN (really)?

IEEE definition are sometimes a bit historical - a wire connecting a node to a switch port is a layer-1 segment (historically, this could also be a shared coax cable with many nodes connected to it, ...
Zac67's user avatar
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5 votes
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Why does STP choose the lowest bridge ID as the root bridge?

Why should we choose the switch which has "the lowest" bridge ID to be the root bridge,not "the highest" ? The reason is simply because lower numbers come first when counting ...
Jesse P.'s user avatar
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5 votes

Why does STP choose the lowest bridge ID as the root bridge?

Why can one of switches has the lower priority?if priority can change,then base on what reason,so we let this switch has the lower or lowest priority ? The position in the topology? the performance of ...
Marc 'netztier' Luethi's user avatar
5 votes

Why does STP choose the lowest bridge ID as the root bridge?

Why should we choose the switch which has "the lowest" bridge ID to be the root bridge,not "the highest" ? One simple reason why Radia Perlman chose lower: Stability Since MAC ...
Ron Trunk's user avatar
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4 votes
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Understanding Linux Bridging

The way switches (bridges) work is that a switch builds a MAC address table which relates MAC addresses to the port(s) where the MAC addresses are connected. When a frame comes into a switch port, the ...
Ron Maupin's user avatar
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4 votes
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Cisco ISO - Are all interfaces assigned to bridges automatically?

By default, all switch ports are in VLAN 1. Since you've assigned VLAN 1 to your bridge group, they would all be a part of bridge group 1. You can assign a switch port to a different VLAN (for ...
Ron Trunk's user avatar
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4 votes
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Bridge for collision domains

A bridge (a switch is a high-density bridge) can help reduce the number of devices in a collision domain by breaking a single collision domain into multiple, separate collision domains with fewer ...
Ron Maupin's user avatar
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4 votes

Can a network bridge be viewed as a two port switch?

In most respects, yes. A bridge may be just a switch, but it may also be more: there are (were) bridges that could connect different MAC-oriented layer 2 protocols like Ethernet, Wi-Fi, Token Ring, ...
Zac67's user avatar
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4 votes
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Upgrading Cisco 819 to 809, can I connect devices to 2 routed ports and be on same subnet?

If your router can use IRB (Integrated Routing and Bridging), you could set up something like this: bridge irb ! <- *** Enable IRB *** ! interface FastEthernet0/0 no ip address bridge-group 1 ! &...
Ron Maupin's user avatar
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4 votes
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What is the effect of having too many bridges / routers between 2 devices?

You might want to consider SFP modules/transceivers integrated into the switches instead of unmanaged converters - SFP modules in managed switches are much better to monitor and troubleshoot. In your ...
Zac67's user avatar
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3 votes

Is there an "active" network tap (not just passive)?

It seems to me that you mis-understand the TAP concept. It only means that you duplicate a link. Then you are able for example : to forward the first TAP output link to the destination (or next hop) ...
vera's user avatar
  • 201
3 votes

Regarding Bridge domain and L2 vpn

So there's likely a whole lot of other things going on with this configuration so the amount of depth that can be provided is going to be limited. To answer your questions specifically- A1: (from ...
rnxrx's user avatar
  • 6,114
3 votes

How transparent bridging Wi-Fi with Ethernet works?

A "self-learning MAC bridge" tracks the MAC addresses from the frames it receives - this way it nows, which frames need to be forwarded to which port. WiFi bridging works the same way. MAC addresses ...
Zac67's user avatar
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3 votes
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Cisco router under workgroup bridge AP

The trick is getting the router to appear on 10/24. DHCP and secondary addressing requires a bunch of VLAN Magic(tm). Assuming no one wants to get that messy... adding routes on the router and ap ...
Ricky's user avatar
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3 votes
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Phone and PC network sharing one wifi bridge

It will work. Keep in mind this to learn why: 1 - A LAN is a single broadcast domain and single collision domain. Collision Domain: It means that a collision will be sensed by all the devices in the ...
jcbermu's user avatar
  • 4,507
3 votes

What is a VLAN (really)?

Specifically answering about whether we implement VLANs without bridging. Without a bridge, this would refer to a subset of stations on a LAN (single segment), although in practice we never ...
jonathanjo's user avatar
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3 votes

Cisco Catalyst 3850 router VLAN bridge no routing

That should be possible - provided that... the same set (or at least a common subset) of VLAN IDs is used across the chain of switches this same (sub)set of VLANs is configured/added on all the ...
Marc 'netztier' Luethi's user avatar
3 votes

What is the bridging decision when getting ARP request?

The ARP request is using a broadcast, so VM2 forwards it across its interfaces. Broadcasts are always forwarded across a bridge. Unicasts are only forwarded when the destination is located on the ...
Zac67's user avatar
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3 votes
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Bridged Mode Networking vs. Network Bridge

Bridge mode is the configuration that disables the NAT feature on the modem and allows a router to function as a DHCP server without an IP Address conflict. Connecting multiple routers can ...
infra's user avatar
  • 3,118
3 votes
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Bridges, hubs, switches and repeaters in subnetting

Hubs and repeaters are layer-1 devices, basically powered cables, that have no addressing. Bridges and switches work at layer-2, and they do not need network addressing to function. Unmanaged bridges ...
Ron Maupin's user avatar
  • 99.6k
3 votes

Bridges, hubs, switches and repeaters in subnetting

You dont assign Ip addresses to hubs, hubs only "forwards" the frames received to the rest of the ports, switches can have an ip addess if you either want to manage it and be able to log in to by ssh ...
Kejimire's user avatar
3 votes

meraki bridge mode: dhcp is untagged

I believe I have found the problem based on how you have described your configuration, but your description wasn't sufficient to provide the information I needed to notice the problem. I ended up ...
YLearn's user avatar
  • 27.3k

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