Network Engineering Stack Exchange
Network Engineering Stack Exchange

Most Popular

more tags
1500 questions
23
votes
6 answers

What stops someone from configuring their network with IP addresses they do not own?

Here's the scenario. I was picturing a university that bought a range of IP addresses. I think their network would still be connected to an ISP (right?), but they'd have freedom to configure stuff the way they wanted. What stops them from assigning…
Tiago Oliveira
  • 553
  • 1
  • 4
  • 8
23
votes
4 answers

What's the difference between `Latency` and `Round Trip Time`?

Golang community provide a HTTP/2 demo website to compare the performance between HTTP 1.1 and HTTP/2. We can choose different latency, e.g. 0s latency, 30 ms latency, 200ms latency. Is latency a terminology of computer science? What does that…
Ryan Lyu
  • 333
  • 1
  • 2
  • 8
23
votes
1 answer

Is a TCP server limited to 65535 clients?

There are 65535 TCP port numbers, does that mean only 65535 clients can connect to a TCP server? One might think that this places a hard limit on the number of clients that a single computer/application can maintain. One could be overseeing a web…
Kind Contributor
  • 883
  • 1
  • 6
  • 14
23
votes
3 answers

What is Link-local addressing?

I noticed that IPv4 reserved 169.254.0.0/16 and IPv6 reserved fe80::/10 for link-local addressing. While I saw IPv6 uses both fe80::/10 address and my private IPv6 address fd00::12 to communicate with other devices in Wireshark, I never seen…
Pue-Tsuâ
  • 666
  • 1
  • 6
  • 20
23
votes
2 answers

vlan 0, 1, and 4095 are reserved: what are they reserved for?

This answer says vlans 0 and 4095 are reserved. Wikipedia agrees that vlans 0 and 4095 are reserved. This article says that Cisco reserves vlan 1 (in addition to vlans 0 and 4095). But I am having trouble finding good information on what are these…
Trevor Boyd Smith
  • 333
  • 1
  • 2
  • 7
23
votes
6 answers

Speed of Light in Copper VS Fiber - Why is Fiber Better?

I'm reading Computer Networks - A Systems Approach 5th ed., and I came across the following statistics for the speed of light through different mediums: Copper – 2.3 × 108 m/s Fiber – 2.0 × 108 m/s So, are these figures wrong, or is there another…
Remption
  • 341
  • 1
  • 2
  • 7
23
votes
3 answers

Protocols: EIGRP vs OSPF

EIGRP and OSPF are both IGP protocols, the former is a mostly Cisco protocol and the latter is a well established open standard. What are the benefits of one over the other? Put another way, when deploying a network, why choose one over the other?…
Lucas Kauffman
  • 4,171
  • 5
  • 29
  • 51
23
votes
10 answers

How to generate traffic for lab scenarios

I'd like to start exploring QoS, and lower level optimizations for things like broadcasts/multicasts within my home lab. I've looked around for ways to generate traffic to and from a box, but haven't found anything to really max out what a given…
A L
  • 3,310
  • 9
  • 33
  • 56
22
votes
6 answers

What, exactly, is required to make Airplay work across VLANs?

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 Airplay is a proprietary protocol which probably…
alx9r
  • 904
  • 2
  • 11
  • 24
22
votes
3 answers

Difference between router and gateway

What is the exact difference between router and gateway? In Network configuration we set the default gateway IP address, but in reality we call the device configured with that IP address as router?
Raja
  • 355
  • 1
  • 3
  • 8
22
votes
4 answers

Why is the CAM table in a switch called CAM table and not MAC table even though it holds MAC addresses?

I know the CAM table in a switch holds MAC addresses and the ports that are associated with the respective MAC addresses. There are no such thing as CAM addresses from my knowledge, so why is it called CAM table and not MAC table?
yoyo_fun
  • 1,531
  • 4
  • 19
  • 28
22
votes
1 answer

How multiple client connections are made to single web server?

Actually I am learning Computer Networks and while at it, I am confused in how a web server maintains multiple connections? Simply to state, I learned trough some googling is that sockets handles a each client request. So lets say there is a web…
Sagaryal
  • 361
  • 1
  • 2
  • 4
22
votes
4 answers

What does a UDP connection timeout really mean?

Since UDP is a connectionless protocol, I'm confused by the setting on my Sonicwall Firewall for "UDP Connection Timeout". It's set at a default of 30 seconds -- but what exactly times out after 30 seconds? Here's my actual real-world situation: I…
Jon Wadsworth
  • 343
  • 1
  • 2
  • 8
22
votes
3 answers

What do TCP/UDP add to "raw ip"?

I know that both TCP and UDP are built on top of IP, and I know the differences between TCP & UDP, but I'm confused about what exactly "raw ip" is. Would it be fair to say that TCP & UDP both implement IP, but that IP in and of itself isn't capable…
John Dorian
  • 323
  • 1
  • 2
  • 5
22
votes
1 answer

All WiFi clients losing connectivity at the same time

In order to provide WiFi coverage for a small office area, a Cisco autonomous single-band 1041 (AIR-AP1041N-E-K9) is used, running software version 12.4.25d-JA1. The access point is having a basic configuration for a single SSID with WPA/TKIP + PSK.…
Daniel Yuste Aroca
  • 2,884
  • 5
  • 24
  • 43
1 2 3
…
99 100