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Top Questions

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42

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7

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9k

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Why are IPv4 addresses running out?

ip ipv4 nat ip-address

answered 23 hours ago Damon 151

12

votes

5

answers

4k

views

Do WiFi and IEEE 802.11 mean the same thing?

wireless ieee-802.11

modified Sep 28 at 16:47 Zac67 21.1k

13

votes

2

answers

1k

views

Serialization and serialization times in 40G/10G and 100G/25G Ethernet

latency serialization rtt 40g 100g

modified Oct 3 at 10:59 jpa 266

8

votes

3

answers

771

views

Is there a performance difference between a managed an unmanaged network switch?

switch switching performance

modified Sep 27 at 14:11 202_accepted 121

4

votes

3

answers

668

views

Do routers change MAC address of packets when forwarding

router mac-address

modified Sep 20 at 13:10 Raimund Krämer 103

5

votes

2

answers

805

views

Ethernet padding value

ethernet

modified Sep 25 at 4:55 Pikamander2 103

5

votes

3

answers

886

views

What is the characteristic of spoofed ARP packets?

network arp security

answered Oct 2 at 7:33 Tom 11

6

votes

2

answers

434

views

Mitigating 802.1x bypass by transparent bridging

security ieee-802.1x

modified Oct 1 at 11:21 Zac67 21.1k

4

votes

3

answers

262

views

Why does it say, that a Switch can segregate the collision domain?

switch

modified Sep 21 at 15:58 Joel Coehoorn 274

1

vote

5

answers

148

views

What is a VLAN (really)?

vlan bridge

answered Sep 28 at 16:50 Anthony 36

2

votes

4

answers

138

views

Does a router always have two IP addresses?

routing dhcp

modified Oct 8 at 16:05 jonathanjo 6,620

1

vote

2

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346

views

What is a “rotary dialer” in the context of dialup connections?

ppp modem dialup

modified yesterday Marc 'netztier' Luethi 2,104

5

votes

2

answers

123

views

Why is internet speed called Bandwidth?

internet bandwidth

modified Oct 3 at 17:09 jonathanjo 6,620

0

votes

5

answers

69

views

Trace the IP address

ip ipv4

answered Oct 5 at 17:02 Peter Green 6,774

2

votes

1

answer

177

views

Cisco Wifi access points roaming

cisco access-point

modified yesterday Léa Massiot 192

1

vote

2

answers

65

views

How does a Layer 2 Switch know which port is a neighboring switch port and which port is connected to a host?

switch switchport

modified Sep 24 at 17:03 jonathanjo 6,620

0

votes

2

answers

91

views

Accessing Internet without WIFI or Ethernet

ethernet ieee-802.11

modified Oct 5 at 6:34 Maverick 1,097

1

vote

2

answers

64

views

Why would pfSense ignore arp requests?

arp pfsense

modified Sep 20 at 17:17 Marc 'netztier' Luethi 2,104

3

votes

1

answer

90

views

Rancid can't download Cisco Configuration

cisco rancid

modified Oct 12 at 17:37 user2968390 16

2

votes

2

answers

67

views

Why can't I get a WiFi password by sending out the same SSID?

router network ieee-802.11 security

modified Sep 23 at 23:04 CellPointNetworks 86

2

votes

1

answer

126

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Config BGP policy for limit ISP path in Juniper MX 480 Router

bgp juniper juniper-junos juniper-mx

answered Oct 5 at 10:17 Teun Vink♦ 10.2k

0

votes

2

answers

57

views

Can a half duplex communicate with a full duplex device

duplex half-duplex

modified Sep 26 at 8:42 jonathanjo 6,620

2

votes

1

answer

104

views

Data link layer acknowledgement

router ethernet osi

answered Oct 5 at 11:44 jcbermu 3,878

0

votes

2

answers

62

views

What are the biggest problem in distributed processing?

redistribution

modified Sep 30 at 17:50 jonathanjo 6,620

0

votes

3

answers

45

views

Cisco Switch ports and MAC addresses

cisco mac-address

modified 2 days ago Ben Personick 111

1

vote

2

answers

94

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How does DOCSIS relate to DVB-C

network docsis

answered Sep 25 at 20:40 Zac67 21.1k

2

votes

1

answer

72

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What is the relationship between throughput and latency

tcp latency throughput

modified Sep 17 at 13:28 Marc 'netztier' Luethi 2,104

0

votes

2

answers

47

views

How do you know which layer-2 protocol is in action?

protocol-theory

answered Oct 7 at 13:06 GGG 1

0

votes

2

answers

60

views

Do I need a Gateway if I try to Ping a Client in the same Network?

network ping

modified Sep 26 at 20:21 Zac67 21.1k

1

vote

2

answers

45

views

Why are the routes taken by packets random using LPM?

routing ip network security

modified Sep 24 at 8:13 yobro97 108

1

vote

1

answer

57

views

Port-forwarding rule on Cisco ASA not working - “Drop-reason: (acl-drop) Flow is denied by configured rule”

cisco-asa nat port-forwarding

modified Oct 6 at 20:23 SamAndrew81 108

0

votes

1

answer

72

views

Finding the source MAC address in Router Advertisements [closed]

network mac-address networking

modified Sep 20 at 7:12 jonathanjo 6,620

1

vote

2

answers

70

views

Re-building an old network

network

answered Sep 24 at 21:18 Zac67 21.1k

0

votes

1

answer

54

views

Is an SBC sufficient and can it NAT

cisco nat voip

modified Sep 20 at 8:20 Marc 'netztier' Luethi 2,104

0

votes

2

answers

68

views

How a packet gets from source to destination or from client to server

routing networking

modified Oct 12 at 20:51 Ben Personick 111

0

votes

1

answer

50

views

Where does DNS resolution fit within the TCP/IP stack?

ip osi

answered Oct 8 at 11:37 jonathanjo 6,620

4

votes

1

answer

48

views

Is it bad practice to use a Virtual Router for NTP-Clustering?

redundancy vrrp ntp

modified Oct 11 at 12:55 jonathanjo 6,620

0

votes

2

answers

47

views

Cannot put an IP address on layer two interface

cisco cisco-ios

answered Oct 5 at 15:12 GGG 1

3

votes

1

answer

60

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40G QSFP+ to 4x10G SFP+ Cable

cisco

modified Sep 30 at 21:49 Ron Maupin♦ 57.8k

0

votes

2

answers

44

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Why ARP need ARP cross LAN request?

arp proxy-arp

modified Sep 18 at 11:58 Zac67 21.1k

2

votes

1

answer

56

views

Guest VLAN doesn't work at wired connection on HP 1920 JG927A

ieee-802.1x

modified Sep 19 at 11:41 Zac67 21.1k

3

votes

1

answer

43

views

What does 'parent interface' mean with respect to VLANs?

router vlan networking pfsense

answered Oct 8 at 6:26 Zac67 21.1k

0

votes

2

answers

52

views

BGP with x2 sessions and x2 L3 VLANs - Please Explain

vlan bgp layer2 layer3 mac

modified Sep 20 at 8:57 Andrey Prokhorov 1,138

0

votes

1

answer

51

views

I want to ping from pc 192.168.1.2 to pc 192.168.2.2 but i am not able to do so. Can someone tell me my mistake

cisco network packet-tracer

modified Sep 19 at 14:03 JFL 10.1k

0

votes

1

answer

30

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Is it possible to back up network devices configs on a RADIUS server (automatically or manual)

radius

modified 8 hours ago Kritesh Anand 1

2

votes

1

answer

104

views

Cisco ASA5516 9.8(2) IKEv2 negotiation aborted due unsupported failover version

cisco cisco-asa vpn site-to-site

modified Sep 20 at 12:36 aledeniz 21

2

votes

1

answer

38

views

How to emuate simple (telnet-like) network protocol with netcat or similar

wireshark

modified Sep 26 at 15:27 eudoxos 151

0

votes

1

answer

28

views

Does gateway have a genmask?

route

modified Sep 17 at 13:12 jonathanjo 6,620

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