Questions tagged [router]
For questions about network routers, devices that forward data packets between computer networks, commonly at the network layer (layer 3) of the OSI model.
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Can you guys help me to find which router is this? [closed]
It has serial, fastethernet and ethernet port.
s0/0 f0/0 and e1/0
It try to use c7206 but it adds the serial s1/0 not s0/0.
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The use of VRF Lite
I have a quick question about VRF Lite.
So I understand that VRF is a technology which allows the router to build multiple virtual routing tables which divide the network on L3 with each VRF table ...
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Simple question about NAT [duplicate]
So I am learning about NAT. I understand that it changes IP from public>private and vice versa. From my understanding, when a packet or info gets sent to the public ip towards the private ip, ...
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How can a router know the MTU of the next router?
https://www.cloudflare.com/learning/network-layer/what-is-mtu/
Suppose Server A and Computer A are connected, but the data packets
they send to each other have to pass through Router B and Router C
...
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Communication between hosts on different local networks
I understand how NAT works in case of communication between one, local host and a server with specific public IP address. The host is sending a request, it pushes the packet with destination IP ...
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IPv6 subnetting with different end device requirements
`I have three main buildings with building A with 242 end devices, building B with 54 end devices and building C with 894 device. And all the routers are connected to each other like ring topology. ...
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RMA'ed device configuration [closed]
Just wondering what are the methods that you use when re-configuring an RMA'ed device.
Do you manually configured all the script that runs on the device or is there any efficient ways configuring the ...
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Why Fast Ethernet port in Cisco Packet Service is always down?
I built a simple network simulation with Cisco Packe Tracer. I am not able to understand why fast ethernet port Fa0/0 on server Gmail and correspondent port on Router2 are always down. I checked and ...
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Router to Wireless router (Packet Tracer)
Hi, Can anyone help why I can't ping from my pc in office network to my laptop in guest network or wireless network. It is possible to ping from guest network to office but failed vice versa.
Main ...
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how does a router know an ip address's network prefix when it comes to CIDR
Let's say I start a new company and lease a block of ip address 222.123.123.0/25 from Internet registry, so one of those ip address 222.123.123.4 is my main web server. A customer from a different ...
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DH groups support for isakmp policy
When configuring a site-to-site VPN tunnel between the ASA and Cisco router, I have queries around the ISAKMP policy. As per Cisco documentation for ASA, the crypto isakmp policy groups available are ...
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NAT configuration behind pppoe with virtual server
my CISCO 3925 router is handling pppoe, NAT, and DHCP server..
My local LAN is 192.168.1.x and it's behind that NAT.
I'm trying to enable access to a DNS server that's on this LAN (192.168.1.191 tcp/...
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Are all router ports both input and output or are ports divided in those two categories?
I've read that router input ports accept incoming packets and that output ports transmit the packets on the link.
However, a link can be used for carrying packets in both ways and in a router there is ...
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Direct connection slower than via switch
My office ISP provides a 1 GBPS connection. When I connect my laptop directly to the router provided by the ISP, and connect to fast.com, I get a speed of approximately 100 mbps.
Our office network is ...
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In MPLS RSVP how would methods of reservations like Wildcard-Filter, Fixed-Filter method, and Shared-Explicit method be explained in simpliest terms?
More specifically I do not understand what is concedered by "transmitter described with wildcard character" in Wildcard-Filter method in RSVP? How is reservation done with this method? What ...
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In what situations is MPLS label erased from the top of the label stack in MPLS?
What are other processes that MPLS/IP routers can do with, or to MPLS label stack?
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How is Control plain in MPLS used for creating label table, and IP routing table?
How is Control plain in MPLS used for creating and maintaining label table, and hold protocols for creating and maintaining IP routing table? Is IP routing table in MPLS located in Customer edge ...
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In router's config, why do I need to advertise the directly connected network?
I have learned that, in routing config, a router must advertise all of its networks.
For example, in this topo:
Router A need to network 192.168.1.1 0.0.0.255 and network 100.1.1.2 0.0.0.255
But why ...
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CISCO cellular Router cannot reach network via my PC
I configured the cellular and my router is connected to the internet ping (5/5) Success
but I still cannot access the internet via PC
Here is my running-conf
Current configuration : 2271 bytes
!
! ...
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Trace Route RTO in two or more hop but next hop works [duplicate]
Today when I was doing tracert,
in the 2nd & 3rd and also 4th Hop I get RTO but my next hop seems to be reachable. How come it works?
Please answer asap.
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What is PPP and why does it not have a MAC address?
I just wanted clarification on what exactly PPP is and why it does not have a MAC address due to having seen that under a response to a question of how routers transverse packets to their destinations....
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What ways are there to make sure router multicast tables are up to date?
I've been reading on IGMP v3 and think I understand the basics of how to join a multicast group - sending a Membership Report Message.
But I'm not sure what the "best" or even conventional (...
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Wireshark filtering, wpa2 handshake type value and other types
I am capturing a wpa2 handshake with wireshark, and there is the type value of 03 which is a key I wonder if this type is constant for wpa2 handshakes, also the value of other types, if there were to ...
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Are there any methods of differentiate between a single computer and a NAT router?
As far as I know, a traffic from a NAT router should appear similar to traffic from one computer with a single IP address. If you do not have any access to a network (let's say you are an ISP), can ...
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If there's a NAT-capable gateway between WAN and a switch, why is a switch helpful?
To preface this question, my question is somewhat related to what I'm trying to understand as the difference between layer 3 switches and routers. The main difference between the two is that layer 3 ...
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If your ISP already has a gateway, why do you need another gateway with NAT to come before a layer 3 switch?
Please bear in mind that I am learning and have never set up a network with routers and switches myself. Also please bear this is sort of going to be loaded question because there are multiple layers ...
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Can you have multiple paths in BGP through different ASes?
In a course about networks in my university, we learnt about how in BGP routes, each AS chooses a single route to each IP prefix (though you may have multiple iBGP routes).
Meaning that in the ...
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For IPv6, How much processing delay difference between using /64 and /127 for Core network interconnection?
I've question about IPv6 routing processing delay.
Lets assume we've got big Core network with huge traffic and many hops.
All router's p2p interconnection addresses are used /127 network.
In my ...
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Sharing same IP address inside LAN? [duplicate]
Q: if 2 devices A and B share same ip address in LAN, can device A retrive all messages whose destination is device B?
I think this depends on how the LAN is configured.
If it's wireless then device A ...
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One layer 2 switch in the middle of router network
In general,
The connection should be like
PC---SW---ROUTER---Many ISP router---Router---SW---PC
so the packet will be from
layer 2 ---layer 3---layer 2
What if I put one layer 2 switch in the network
...
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Can 2 modems connected to the same router interfere with each other if their web access interface are the same IP address?
Here is information about the network:
I have 2 WAN connections to the same ISP which they provided 2 modems
for and configured them to be in bridge mode.
My MDF router (pfSense) connects both of ...
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Customized IPv6 packet with multiple inner data fragments for multiple destinations
I am studying the possibilities of using IPv6 potentialities to design a customized IPv6 data packet that has the following features:
1. Combines many fragments of different data in one packet.
For ...
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Cisco IR829GW - Stuck booting into Rommon Mode 2
No confreg commands are recognized. No set variable commands are recognized.
At first I was able to factory reset the router and go into the initial configure boot menu options, then from there I ...
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My PCs aren't able to ping each other successfully. Why? I think my Ip route is the problem? I am not sure
I have a topology of PCs A, B, D, and E, 2 routers R1 and R2, and 4 switches A, B, D, and E for each of my PCs respectively.
PC A IP is 201.4.100.1/28 with a default gateway of 201.4.100.2,
PC-B IP ...
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Is it possible to set maximum 32 PAT translations per global ip address?
So basically I'm trying to configure a cisco router (c7200) to use PAT with a pool of global addresses, and each global address should only support a maximum of 32 private addresses.
I've been ...
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How to properly configure OSPF protocol?
I have this simple 3 router network that I need to configure the OSPF for, when using two routers every thing works fine and i can ping but when I add the third router nothing works
left router
...
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GNS3 Router Telnet Configuration
I configured the IP address and telnet for my Cisco router but on GNS3 it shows a different IP address. When I ping the router from my Ubuntu virtual machine using the IP address I configured the ping ...
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Is BGP always required when you have multiple ISPs?
I am trying to understand when is Border Gateway Protocol needed and I stumbled upon this question:
When is BGP needed?
The chosen best answer says:
You could peer with your service provider and ...
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Public IP Configuration which has a private gateway
I bought a public IP from my ISP and they provided me with the following details.
WAN IP :10.129.69.157
LAN IP : 196.188.173.32/30
How do I configure this on my side ?
The told me to do configure as ...
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Does a router need ARP to send data to router in anther netwrk, it already has the IP address of the interface right?why does it need the MAC address? [duplicate]
i am studying off this
https://www.practicalnetworking.net/series/packet-traveling/key-players/#arp
but my question is if ip address is for end to end communication , how is the end to end happening ...
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WiFi password: What is the exposure? Is it only local or can WiFi password be used remotely somehow?
(As everyone does) I have a local WiFi password that is used for signing in and using the WiFi for local users.
I have a separate & far stronger (64 char) admin password to gain access to my WiFi ...
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How to correctly setup a DHCP server in the following network?
So, I've got the following Network Configuration:
Assume that, on the graph, "PCs" can be any device that needs an IP(apart from a router).
Now, as explained on my title, I want to run a ...
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How ARP works [Specific Case]?
After reading about ARP and NAT I'm really confused about putting them to work together.
Let's suppose we have a router A with a public IP of IP(A). Plus, 2 devices behind that router B and C, each ...
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What happens if the layer 2 destination MAC address mismatches?
I was wondering, what happens if I send a packet with layer 2 destination (say 1ebf) different that what will receive it, lets say a router (mac 22ff) recieves it. Will it drop the packet? Or ...
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Is it okay to not assign an IP address to the physical interface of router when used for "Router on a Stick"?
When setting up "Router on a Stick" interVLAN routing, the steps I have seen only covered creating sub-interfaces for each VLAN and assigning an IP address to each of these sub-interfaces. ...
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Does each computer/smart phone use electromagnetic wave with different frequency to communicate when they're connected to a WLAN?
I read some papers about WLAN and Wi-Fi. They say that modern WLAN/Wi-Fi uses a kind of technology called "OFDM(Orthogonal Frequency Division Multiplexing)".
My understanding is: ODFM means ...
user85401
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Is the header of any other layer (other than the Data Link layer) is also removed and re-added when reaching a router?
Based on my understanding, when a packet reaches a router, the Data Link layer header (and trailer if there is a trailer) will be removed from the packet and a new header (and a new trailer if there ...
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Does a router need to have an IP address?
Does a router need to have an IP address? if the answer is yes, then what is the router IP address used for (one reason I can think of is NAT, but not all routers are used for NAT)?
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Do all routers have two IP addresses?
I know that a home router have a private IP address and a public IP address, but what about the routers that an ISP uses, do these routers also have two IP addresses?
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In what situation would normal choke packet be preferred over hop-by-hop choke packets?
When the host is far away, it makes sense to use hop-by-hop choke packets to resolve congestion.
But is there situations where normal choke packet is more appropriate?
And by the 'source' we mean a ...
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