All Questions

Filter by
Sorted by
Tagged with
0
votes
1answer
21 views

Is SONET a physical layer or a data link layer?

According to some sources, SONET is physical layer. But some sources say that SONET can carry IP directly. Also, SONET defines its own frame -- it has a header and a payload. That must make SONET a ...
0
votes
2answers
43 views

Congestion control in transport and network layers in TCP/IP

Why do we need congestion control in BOTH the transport layer and network layer in TCP/IP model. Cant we be good enough with control in just one of the layers only? And how do they differ?
2
votes
3answers
313 views

What is the difference between an ASA firewall and UTM firewall?

How do ASA firewalls and UTM perimeter firewalls differ?
-1
votes
1answer
37 views

IPv4 and IPv6 Source Address field

Both the IPv4 and IPv6 headers contain the source address field. What are the reasons for including this field? Is it for to trace which who sent this packet if it get's lost?
2
votes
1answer
37 views

what is significance and role and function lifetime in IPSEC Site to Site VPN . Please explain importance and role of lifetime in VPN

I Came across incident where i need to troubleshoot IPSEC Site to Site connectivity issue . The term "lifetime" confuses me . please anyone explain me importance of lifetime in VPN . Whats ...
0
votes
2answers
27 views

Ping responses to the Gateway

Last week, I have experienced a strange scenario with Adtran NV3448(a router) and an ISP circuit. Adtran is a similar company like Cisco, also makes networking equipment such as Router, switches, etc. ...
0
votes
0answers
11 views

How does the IPv4 Total Header Length field & Fragmentation work together? [duplicate]

I recently learnt that the maximum value of the IPv4 Total Header Length field is 65,535 which equals approx. 65.5KB. To my understanding, it is different from the IHL field as it includes the ...
0
votes
1answer
21 views

Access IPSec site from another IPSec site

Our company delivers, installs and maintains custom build hardware at customer sites. In all cases the delivered setup contains at least 1 server and 2 network devices. To keep the control over the ...
-1
votes
1answer
44 views

Simulation of a large network by GNS3

I want to simulate a large network of 40 routers with GNS3 or OPNET or VIRL or … In the real network, routers route their incoming traffic (coming from an external network) and deliver it to an ...
0
votes
1answer
15 views

What can I use to display VPN instance instead of stelnet?

How can ı connect VPN service with use ssh in Huawei Atn980c ? Which command? I researched but i didnt different command. I found only this command; stelnet x.x.x.x (VPN instance) (service name) (port ...
1
vote
2answers
32 views

Query regarding LACP System Priority

This is regarding LACP System Priority. From my research I could find the following info pertaining to system priority. LACP combines the System Priority value with the MAC address of the switch to ...
1
vote
2answers
58 views

Do X.25/Frame Relay/ATM/MPLS have their own switches?

In the context of networking when we say "switch" we always think of Ethernet switch. But do we have X.25 switch, Frame Relay switch, ATM switch, and MPLS switch? If yes, how are they ...
0
votes
1answer
46 views

How is ICMP Packet Too Big handled in IPv6?

I am trying to comprehend the way packets fragmentation works in IPv6. As far as I understand it, IPv6 routers never fragment packets: upon receiving a packet whose size is bigger than the MTU of the ...
0
votes
1answer
17 views

Query regarding LACP timeout flag

Say we have two swicthes. Switch A and Switch B. Switch A sends LACPDU's with timeput flag set to 1 (fast). Switch B sends LACPDU's with timeout flag set to 0 (slow). By researching came to know that ...
0
votes
0answers
20 views

Queries regarding LACP

I have following queries regarding LACP. Query 1 In LACP flag we have a field called as Aggregation, where 1 represents Aggregatable and 0 represents Individual. In all the PCAP's I have seen so far ...
1
vote
1answer
57 views

How does “bits per second” relate to wavelength?

I'm learning about optical networking at a new job, and am confused by some introductory terminology. I'm pondering this statement: There is typically one transponder for every client signal and SFP ...
0
votes
1answer
28 views

Make eBGP and iBGP equal in Juniper MX204

Apologize for the dumb question, I come from the server world. Our network admin is on holiday and I'm filling in. For the sake of simplicity, we have a fairly symmetric traffic pattern, what goes up ...
2
votes
1answer
33 views

Junos not automatically advertising an address configured on loopback interface to OSPF

According to JNCIP study guide(page 156) from 2003, the Junos should advertise a prefix on lo0.0 interface to OSPF if the RID is not manually configured: JUNOS software automatically advertises a ...
1
vote
2answers
30 views

How does ISP service cancellation work? [closed]

I'm learning about networks, and so far the more I know how computers and routers are connected, the more doubts I have. I understand I'm plugged via ADSL to my ISP's routers and servers, however, I'm ...
0
votes
2answers
53 views

NATTing a server address

I need help writing NAT rule for this use case: I want to be able to connect to an local IP as though it's the remote server IP. e.g. port forwarding. I don't have access to the firewall on the remote ...
0
votes
0answers
23 views

Issues (and spec check) regarding terminating solid core ethernet cable

Tomorrow I'm installing a TP-Link TL-SG1008MP 8-Port Gigabit PoE+ Ethernet Switch to an existing network, powering a TP-Link OC200 Omada AP controller and three TP-Link EAP225-Outdoor access points ...
12
votes
3answers
4k views

Why isn't multicasting more popular?

Multicasting seems provide an efficient method of routing networking traffic from a source to multiple end users, especially at this moment in time with teleconferencing, streaming media, online ...
0
votes
1answer
43 views

Suspect MTR showing incorrect packet loss through router; other tools are not showing loss

Using MTR (sending TCP with or without SYN), I'm consistently seeing packet loss on one intermediate router in the path. UDP does the same. I'm use TCP to avoid the ICMP packet flood limits set. I ...
0
votes
1answer
27 views

IP datagram route through a network utilizing ARP

Suppose I want to send an IP datagram from node D to node C . Each step I also want to list the MAC addresses of the source and the destination , as well as the source and the destination of the IP ...
0
votes
1answer
21 views

Propogation delay vs time required to send out a complete frame on channel

I was reading Data Communications and Networking by Behrouz A. Forouzan in which for simple Aloha protocol the vulnerable time given was T(fr) (time required to send out a complete frame on the ...
0
votes
2answers
32 views

how to move configuration from one Nexus interface to another?

I am doing some cleanup on a Nexus switch I have (3048) and was wondering if there was an easy way to copy or move a configuration from one interface to another? When I move an existing connection to ...
1
vote
3answers
54 views

Criteria to match for lacp status to come up

I did research and found that below are the minimum requirements for LACP to be Up. One of the side should be active. All the port speed should be same. Duplex settings need to be same. Also I have ...
-1
votes
0answers
20 views

How can an 10.0.0.4 IPv4 Address be classified as Class A if it's surely a Class C address due to a subnet mask of 255.255.255 (/24)? [duplicate]

I've been studying for the CCNA using Jeremy's IT Lab's awesome course on YouTube. However, there is one seemingly contradictory detail in my mind regarding the IPv4 Address Class that was taught; if ...
0
votes
2answers
49 views

Cisco Router on a Stick IP Addressing

I have been running into IP addressing problems with my Packet Tracer network and VLAN assingments. I have 2 switches connected to a router, 1 switch has 4 VLAN's and the other has 3 VLAN's I can't ...
0
votes
4answers
81 views

How common it is to see unknown IPs in logs?

I have a server that streams video to YouTube/Twitch. I see [UFW BLOCK] entries in logs. One IP is 220.133.236.166, the other is 194.26.25.8. Is it a common thing that a server is connecting to my ...
0
votes
0answers
11 views

Why does sub-netting not give us more addresses? [duplicate]

Sorry if this is dumb, but I am very knew to learning about networks. Here is my reasoning? Let's take the address, 24.50.12.4 if we subnet it with /16 then the network address is 24.50 + host is 0.0....
2
votes
2answers
96 views

What will happen if a server receives a duplicate SYN for an existing connection?

If a server receives a fresh SYN packet for a connection that is already established, what should it do? I have already seen What will happen at server side if it received 2 SYN packet from the same ...
0
votes
0answers
17 views

SNMPv3 context on IOS-XE does not seem to work with Prime

We recently switched to SNMPV3 and experience the issue, that there is no client data available within prime anymore. So we quickly read about the SNMP context we need to add to our devices ...
1
vote
3answers
302 views

Routing between completely separate private networks

I’ve got a request from a partner vendor in a completely separate routing domain to directly route a /24 rfc1918 network on my rfc1918 internal network. The proposed solution has their handoff ...
0
votes
0answers
33 views

What are difference between SSL VPN and IPSEC Site to Site VPN [duplicate]

I am little confused between SSL VPN and ipsec site to site VPN packet flow and authentication methods and moreover what are significant difference between two VPNs . As per my understanding IPSEC ...
0
votes
0answers
13 views

OSPF Router ID election query [duplicate]

I have a query regarding ospf router id election. Suppose I have a router with 3 connected interfaces. 10.1.1.0/24 11.1.1.0/24 12.1.1.0/24 I have enabled ospf area 0 on network 10.1.1.0 and 11.1.1....
0
votes
1answer
34 views

Ethernet Frame visualization

One IP packet is fragmented in multiple ethernet frames at sender's side And at receiver's end, all the frames are combined to get back the IP packet So is there any way to see what payload each ...
1
vote
3answers
78 views

Is there a rigorous difference between a WAN and a LAN?

The main WAN (wide area network) of this world is the one named "The internet" although there might be others I don't know of. Contrastingly, there is no "main" LAN (local area ...
2
votes
0answers
21 views

Please Explain me traffic flow between two peers for ipse site-site vpn traffic , detailed traffic flow please [closed]

please explain me the exact traffic flow between two peers or gateways for IPSEC Site-Site VPN .Like phase 1 ,phase 2 , actual data processing traffic flow .
0
votes
0answers
9 views

How to find Best Fit Mask [duplicate]

How does i find the best fit netmask (i.e., resulting in as few host addresses as possible) for a network with 62 hosts in it? I don't have any class like A,B,C How can i find best fit netmask for ...
0
votes
1answer
28 views

How might ARP impact the UDP communication and what is a scenario i can reproduce to check/understand it?

I was wondering which impact the ARP protocoll might have on a UDP communication. I am learning for an exam and trying things out with mininet (linux )/ wireshark to understand the dependencys between ...
0
votes
1answer
33 views

Why there's no “show vlan” command on my Cisco NCS-5001?

I'm trying to learn my way around Cisco switches by watching an online course [1] and trying the commands from there on a switch I have access to. One of the first commands I've tried, show vlan ...
1
vote
1answer
23 views

Show 'all' routes to a given prefix on Juniper Router

Forgive me if I'm not using the correct terminology here but I'm on a Juniper MX204 router, call it router A. I'm receiving full table from my ISP. I do a show route, i.e. show route 1.1.1.1 and I ...
2
votes
1answer
49 views

Can a QSFP28 port break out to 4 SFP+ ports to separate hosts?

I apologize in advance because I suspect this is already covered. I've read some of the posts and I suspect the answer is "it depends on the vendors involved" or just "no". I'm ...
0
votes
2answers
63 views

Why does IPv6 NS not use unicast address but multicast

This is a follow up of Why not put unicast address in IPv6 packet containing NDP neighbor solicitation instead of solicited-node multicast address? The accepted answer makes no sense. It states the ...
0
votes
2answers
29 views

F5 Policy Based Routing - how do you change next hop without any conditions?

I'm trying to change the nexthop for a virtual server in F5. I have read this article. I have tried using the this irule { nexthop internal 10.10.0.2 } by itself and it doesn't work. I also have ...
0
votes
1answer
15 views

answer packages rejected between mangle/prerouting and nat/prerouting

I am currently configuring a ubiquity edgerouter for our network. We have one uplink port (eth2) and two internal ports (eth0; with vlan 1) and eth3 (with vlans 2,3 and 4). uplink and vlan 1 have ...
0
votes
1answer
34 views

When I send the ICMP packet with 4000B, but the IPv4 segment calculated 4008B

When I send the ICMP packet with data size as 4000B for testing the IP fragment. ping 192.168.2.1 -c1 -s4000 and the Wireshark captured it, Whether is is because of ICMP header? but we know ICMP ...
0
votes
2answers
27 views

What's the Destination unreachable ICMP packet(ICMP payload the UDP) usage? [closed]

In my Mac(192.168.2.228), it will send ICMP packet to my house's router (192.168.2.1). with the info Destination unreachable (Port unreachable) and in the Wireshark packet detail panel, there ...
0
votes
1answer
47 views

Cisco L2 switch port ACL options

I'm trying to understand Cisco Switch ACL options I can potentially use to limit traffic. Switch is a IE2000 series with Lanbase IOS. It is L2, with trunk port to uplink switches, multiple VLANs on ...

15 30 50 per page