Network Engineering Stack Exchange
Network Engineering Stack Exchange

Most Popular

more tags
1500 questions
9
votes
4 answers

What use are MAC addresses?

I know that MAC addresses are used in networks for several things, e.g. static fixed IP addresses assigned by DHCP servers or for Wireless access points. But why is it necessary in the Internet? Let's say I send a packet to someone not on my local…
hgiesel
  • 307
  • 3
  • 10
9
votes
5 answers

Why is the protocol field part of an IP header?

Note this is not a duplicate of Why is the IP layer aware of higher layers in the network stack? The need for a protocol identifier (eg. the IP header's Protocol field) in packet-based communication is clear: It's either this or some sort of…
Docom
  • 117
  • 1
  • 1
  • 5
9
votes
1 answer

EIGRP FD not the same in topology table

In EIGRP when showing topology table, i notice in some entries are like below: P 10.1.6.0/24, 1 successors, FD is 793600 via 10.1.2.2 (2195456/281600), Serial0/0/0 via 10.1.3.2 (77081600/281600), Serial0/0/1 It seems the…
user1559625
9
votes
3 answers

10 Gb blade question

I am debating with a colleague about a potential configuration. We are implementing a new blade solution that has a built in 10 Gb switch and two blade servers, each having 4 10 Gb NICs. However, the rest of our environment is still 1 Gb. The blade…
Ryan
  • 91
  • 1
9
votes
4 answers

Advantage of layer 3 switch over Router

What is the advantage of Layer 3 switch over the Router ??
Abiral
  • 489
  • 1
  • 5
  • 11
9
votes
3 answers

Cisco NAT hairpinning

I have a Cisco router configured NAT (4 static NAT and dynamic NAT). My problem is that I can't access internal servers using public IP addresses from the internal network. I know what the problem is. I did a lot of Google searching about this…
sareeshmnair
  • 253
  • 1
  • 3
  • 8
9
votes
2 answers

Why do summary routes get a low Administrative Distance?

Why do summary routes get a lower AD than other routing protocols? For example: The AD of EIGRP is 90, whereas the AD of a summary route is 5.
Abiral
  • 489
  • 1
  • 5
  • 11
9
votes
4 answers

SCP lost connection

Occasionally I have an issue when I try to SCP a file to one of our Cisco devices. When the connection starts, it immediately drops and says "lost connection". I've had this happen when there wasn't enough space on the flash drive but this isn't the…
some_guy_long_gone
  • 3,052
  • 1
  • 19
  • 30
9
votes
2 answers

Switch-Assisted Load Balancing w/ Fault Tolerance

While studying for Cisco and Microsoft certifications I read a lot about NIC Teaming, Etherchannels and similar stuff. I know you can do static teaming in MS Windows Server or creating a port-channel in Cisco or use Dynamic protocols such as LACP…
Alex
  • 837
  • 2
  • 10
  • 24
9
votes
4 answers

High latency during downloads

I am having the same issue on my business connection 5Mbps as in another posting on this site. As soon as any computer starts a download the latency on the first hop past our DFG provided by our ISP (Bell) goes off the chart. This first hop is…
SA-KRP
  • 91
  • 1
  • 2
9
votes
2 answers

QoS woes - managed IP VPN

(First of all, I'm sorry for this wall of text. I don't know how to make it any shorter without losing important information. I originally wanted to use the chat room for this, like we do on serverfault for these kind of questions, but there is…
pauska
  • 422
  • 6
  • 15
9
votes
4 answers

Network Byte Order

According to big endian byte ordering or network byte order the bits are transmitted in this order: bits 0-7 first, then bits 8-15, then 16-23 and bits 24-31 last. Does this means that bits from version, identification, TTL etc go first and then…
MUSR
  • 536
  • 1
  • 6
  • 17
9
votes
4 answers

BGP - how does IGP know the right route?

Let's consider a host A in an autonomous system AS100. Suppose it wants to communicate with host B in another AS, say, AS200. In AS100 there are several routers. Within one AS, the rotuing protocols used are Internal gateway protocols such as OSPF…
user4205580
  • 455
  • 3
  • 10
9
votes
5 answers

How many IP addresses can a device or an interface possess?

Can one IP address be assigned to more then one device or interface? In which situations may this happen? Can one device or interface posses more than one IP address?
user15062
9
votes
3 answers

How are MAC/IP addresses used in routing

I have to teach my sixth form about MAC Addresses and IP Addresses in a few weeks time and there are some areas I am unclear on which I am hoping some of you will be able to clarify for me. I have enough to get them through the syllabus, but I like…
Robert Flook
  • 231
  • 3
  • 5
1 2 3
…
99 100