Questions tagged [ipv4]
For questions about Internet Protocol version 4 (IPv4); as specified in RFC791.
900 questions
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Nested Fragmentation [duplicate]
If fragmentation only occurs once I can reassemble the package, what if the package is fragmented more than once
For example, a package of 3000 bytes will be sent via an Ethernet MTU link of 1500 ...
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How to identify if there are two devices with same IP adress on a network? [duplicate]
Does somebody know a way how to detect if there are two different devices with same IP-adress on network?
Let us say we have a large network, but there are by mistake two devices with same IP-adress:
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Direct Peer IP, Next Hop Latency is Different based on the destination [closed]
I’m experiencing a network issue with one of my BGP peers, and I need some help understanding the root cause.
Notes: Public IPs i provided is random just to describe the issue
I have a BGP peer for ...
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How dangerous is Class E, really? [duplicate]
On a bar conversation, someone told an anecdote about not being able to jump on a vpn as the private space was the same as the free wifi at the airport. And, after a thinly veiled competition of who ...
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Fragmented IPv4 TCP packet: which header fields (if any) are copied to all fragments?
When a TCP packet is fragmented, are all of its fields (source / destination port, sequence / acknowledgement numbers, data offset, reserved, flags fields, etc.) copied to its fragments? Or does only ...
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IP MTU and Interface MTU
So im facing a problem with understanding which MTU(ip MTU or interface MTU) is the one responsible for fragmentation. I know that ip MTU is at layer3 and interface MTU is at layer 2.just an example: ...
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was there supernetting before CIDR or were subnets restricted to their classes
We know that subnetting before CIDR involved sub-dividing classful networks So subnets of class A, B and C. But with CIDR we can have arbitrary prefixes. For example, 192.0.0.0/7. Could we have done ...
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What does a byte-boundary mean in this example from Tanenbaum's book on subnetting? [duplicate]
To make CIDR easier to understand, let us consider an example in which a
block of 8192 IP addresses is available starting at 194.24.0.0. Suppose that Cam-
bridge University needs 2048 addresses and is ...
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Network Socket Address format used in Cisco ASA syslogs
I'm getting syslog logs from CISCO ASA where the ip addresses are coming in what I would call a non-standard format: The IP with port is being logged as 'd.d.d.d/port' (e.g. 10.0.1.2/63313') so it ...
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In IPv4 Fragmentation, should the first block be necessarily the closest smaller multiple to 8
Is it mentioned in any RFC's that when one is splitting a Datagram into fragments, the bytes in the first fragment should be "the closest multiple of 8" or is it just a standard ...
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Nested Network with same IP Space
I have a router (Teltonika RUT) that is connected via its WAN port to a network (let's call it "Big").
The IP Space of the "Big" Network is 192.168.1.0/24 with the Gateway on 192....
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How localhost and its opposite 0.0.0.0 works
Here I am running an application on a computer, host=localhost, the application runs on localhost:5000, or 127.0.0.1:5000.
When the computer accesses 127.0.0.0/8, or 127.0.0.0 subnet mask 255.0.0.0, ...
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Name for this network range formatting?
I'm working with an FTP server that only accepts IP ranges in this format:
192.168.128-255.0-255
What's the proper name for that format or presentation ?
It is none of:
CIDR: 192.168.128.0/17
Subnet ...
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Update IP Whois Objects using RIPE.net API
So I've searched around RIPE.net and other sources, haven't been able to find an example of how I can do this, as I am not an ASN operator etc.
I've essentially got my RIPE.net Account added to some ...
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What exactly does the term "main network" mean in subnetting?
In the computer networks course, we solve subnetting questions together with the teacher. There is a term we call the "main network". As far as I understand, we fill in this according to ...
