Questions tagged [subnet]
Questions relating to IP subnetting, including planning, calculation and best practices.
643 questions
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Why do we still need NAT pool network mask when we already have starting IP and ending IP?
When configuring source NAT in cisco device
for the command that create nat pool
ip nat pool MYPOOL 203.0.113.10 203.0.113.20 netmask 255.255.255.0
Why do we still need NAT pool network mask when we ...
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Is 223.1.2/24 (sic) correct way to label a subnet?
I ask this because I am reading a famous book Computer Networking, A Top-Down Approach 8th edition, by Kurose and Ross.
On page 352 (pdf) I have this paragraph:
The mentioned figure 4.23 looks like ...
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How to extend current home network to span 2 subdomains? [closed]
I currently have a 192.168.7.0/24 network, but I am approaching 200 devices on it (mostly IOT automation doodads), Id like to spill over into the next subdomain over (192.68.8.0), for this from what I ...
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Isolate a subnet for Azure SQL server so it is not publicly accessible
TL;DR - How do I isolate a resource in an Azure subnet so that it is not publicly accessible, but is accessible from other subnets in the same VNET?
Apologies if this isn't the correct site; this is ...
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Open port X becomes filtered after port-forwarding
There is a device with an ip address of 172.31.1.122 that is connected to a switch (Scalance 8008) and the switch is connecte to a router (scalance s615 which I cannot configure and has ip of 172.31.1....
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Is mask 255.255.255.127 used anywhere? [duplicate]
I am still learning and I've found that there is a formula to calculate: 2*n - 2(where n is number of zeros i.e. digits of hosts).
I am trying to calculate for mask: 255.255.255.127
I've converted it ...
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Subnetting Question Doubt , Check Body [duplicate]
A college was assigned a single block starting with 103.114.1.0/24,
create 3 subnets for 3 departments
a. 150 addresses for computer science department
b. 80 addresses for electrical engineering ...
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How do ISPs assign /29 public IP subnet on a single Ethernet/Fiber connection?
I recently found out the ISP provides a /28 public IP subnet to a business. I'm in the process of learning more about networking and find it interesting that 16 addresses are available through that ...
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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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Should a router behind the internet gateway run source NATing or masquerading if the gateway router is masquerading?
Edit:
On a multi-router network, should a router (R2) behind the internet gateway (R1) run source NATing or masquerading if the gateway router is masquerading?
At this time I can ssh from a host on ...
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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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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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Computers on different subnets can't talk to each other
I'm teaching an introductory computer engineering course in HS and had students in the lab network together the computers they built in the hardware unit - I appreciate the irony of somebody teaching, ...
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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 ...
