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A numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication.

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Subnetting Access Problem

I am learning subnetting, and I am using Packet Tracer to design a network for a building with five storeys. I have used subnetting, with each floor having its own subnet. As a result, it is not ...
3
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2answers
56 views

Whether we usual use dot-decimal notation to represent network or IP by opposite mask?

Whether we usual use dot-decimal notation to represent network or IP by opposite mask? 10.10.10.0 0.0.0.255 # a network 10.10.10.0 255.255.255.0 # a IP Update if we represent a network, we can use ...
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0answers
14 views

How long are Verizon IPs leased for? How often are they re-used? [on hold]

I work for a delivery service and we recently noticed that one of our drivers had a higher than usual number of un-deliverable cash orders, which we allow the driver to keep at the end of the night. ...
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0answers
17 views

IP address conflict according to Linksys [closed]

Apparently my Arris SB8200 Modem is causing an ip address conflict with my Linksys AC2200 Velop Mesh Router. The web gui address for the SB8200 is 192.168.100.1 and Velop is 192.168.1.1. According to ...
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0answers
10 views

Calculate supernet of host and host number based on IP and mask? [duplicate]

So I got the following IP: 192.15.205.7 and the following mask: 255.255.252.0. Now I know that in order to get the supernet of the host I have to use the AND operator between the IP and the mask. In ...
8
votes
1answer
671 views

What is the use-case of including the IPv4 address in IPv6 address?

It is possible to include the IPv4 address into IPv6 address. For example, 2001:db8::c0a8:6301 where last 32 bits are IPv4 address 192.168.99.1. There is even a special notation of IPv6 address where ...
3
votes
2answers
68 views

How to find the switch IP address based on MAC address?

On PC, the extra network adapter is configured as static 192.168.2.1. A switch with DHCP enabled is connected to 192.168.2.1 and if I login using the console (RS232) I see that it has 169.254.x.x ...
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0answers
29 views

Different DNS resolution for same domain name [closed]

I am getting different DNS resolution for www.google.com. When I am using Google Public DNS i.e 8.8.8.8 then by using nslookup then it is giving IP address of Non-authoritative answer: Name: www....
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0answers
30 views

Can you explain this IP address/subnet question? [duplicate]

If I have an IP address and subnet mask combination of 192.168.204.255/24, and my default gateway for a network is 192.168.204.254. How can I make so that I can connect to the network? I'm failing to ...
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3answers
82 views

How did one go from IP to MAC in classful networks?

This is more of a question asked out of curiosity than for practical reasons, but it's bugging me, because it might point to a lack of understanding elsewhere. Back when classful IP addresses were ...
55
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7answers
14k views

Why are IPv4 addresses running out?

I understand that we are running out (or ran out already?) of IPv4 addresses, but I don't really understand why that is. Right now, every home has its own IPv4 address (dynamically assigned, but still,...
0
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1answer
42 views

Replacing IP address of connections from AWS towards SIP

We have installed a PBX on AWS and connected it to our on-prem Router via VPN. My on-prem router is connected to the SIP provider via a physical connection with another on-prem MUX device (device ...
4
votes
6answers
483 views

Why is classful addressing considered waste?

I am trying to understand the addressing strategies. But there is something which I can't grasp. Maybe I am missing a very basic point, if so, I am sorry beforehand. From my researches, let's say, if ...
4
votes
3answers
105 views

How to prevent IP conflict when using VRRP

We are currently using VSRP (Layer2/3) where we have a single IP as the gateway per VLAN. We are considering moving to VRRP (Layer3) which requires 3 IPs, 1 virtual and 2 real ones. This means that ...
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votes
1answer
39 views

How are IP addresses assigned? [closed]

1) If I buy a new computer, I haven't connected to the internet yet, don't I have ip address? 2) if I get the ip in one county, IANA gives me the ip depends on my location (first numbers), if I ...
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0answers
3 views

Is it commonplace / accepted to change an existing CIDR prefix to meet certain network requirements? [duplicate]

Say for example, you have an IP address with a CIDR prefix of /27 (mask of 255.255.255.224) and are required to create 4 subnets each with an equal amount of usable host addresses, would it be ...
0
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1answer
22 views

How to use a remote shell on a machine outside of network

I understand the differences between LAN and WAN addresses. My question is: while outside a network, how do you target a specific machine's address beneath a public IP? Since a public IP for each ...
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1answer
76 views

What is AWS ELB IP range for white listing in firewall? [closed]

I have AWS infrastructure running over AWS ELB (Classic Load Balancer) and EC2. I need to know IP range for AWS ELB in EU (Ireland) Knexusplatform-Live-SaaS-IR-1436765642.eu-west-1.elb.amazonaws.com, ...
0
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1answer
78 views

How to assign 2000 addresses starting from 198.16.16.0? [duplicate]

This problem comes from Tannanebaum's CN book and the full description of it is as follows: A large number of consecutive IP addresses are available starting at 198.16.0.0. Suppose that four ...
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3answers
69 views

Why do we need an ethernet MAC address? [duplicate]

Don't think it's a duplicate. I've searched really many articles and couldn't find the satisfying answer. I understand : how ARP works MAC address is an unique address for each NIC IP is network ...
1
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1answer
45 views

Do RIPE Atlas probes need a public IP address?

I'm new to networking in general, and have only a vague understanding of network topologies. Looking at the RIPE Atlas info video, it would seem that any user can install a probe and that then gets ...
0
votes
1answer
33 views

Assigning IP Address ranges - Protocol, Best Practices [closed]

I am looking for standard procedures when assigning a range for static ip addresses. Which are the most commonly used approaches and why. I am trying to look on the internet and this forum, however ...
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2answers
50 views

Why router interface need IP addresses while IP is constant during the journey?

A beginner question, I've recently read in Cisco CCNA R&S 200-125 official cert guide that the packet leaves the PC with a destination IP of PC2 (the target) but with the MAC of PC2 in case of PC2 ...
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1answer
445 views

Find subnet prefix/CIDR from IP address and required No of hosts [duplicate]

I want to know that how can we calculate the Subnet prefix and CIDR, when the given information is only IP address and required No of hosts. For example: Suppose we have: IP Address= 198.1.1.0 and ...
4
votes
2answers
985 views

Why we use 224 as multicast address in many protocols?

I see in many protocols we use 224 multicast address as like eigrp uses 224.0.0.10 ospf uses 224.0.0.5 224.0.0.6
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0answers
7 views

How to find subnet mask using First and last usable IP address [duplicate]

The first and the last IP addresses of a subnet are 192.192.8.0 and 192.192.63.255 respectively. how to find the subnet mask?
2
votes
1answer
363 views

Can a 172.168.10.0/28 be a class B Subnet

I am starting my studies in networking and starting off with the basics of IP addressing and Subnetting with CIDR values. My Question here is 1st how can you tell the subnet class of an IP address ...
0
votes
1answer
49 views

How ARIN IP Address is used in APNIC Region? [closed]

Amazon AWS provides the following JSON (Source) which has list of IP Address ranges used by AWS. { "ip_prefix": "54.179.0.0/16", "region": "ap-southeast-1", "service": "EC2" ...
0
votes
1answer
86 views

What are the component names of CIDR Prefix Notation?

What are the components of the IETF's CIDR Prefix Notation called? 172.16.0.0/16 contains two parts: 172.16.0.0 /16 In the RFC the entire term 172.16.0.0/16 is defined as the "Prefix Notation" for ...
2
votes
2answers
82 views

Bad mask for Cisco simulator GNS3

I am using the GNS3 simulator, and I need to connect two Cisco C7200 routers. When I enter the ip address 126.0.0.4 255.255.255.252 command, I get Bad mask /30 for address 126.0.0.4.
4
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1answer
136 views

IPv6 - ULAs - Am I understanding use correctly?

Tinkering more with IPv6 and trying to unlearn the IPv4 stuff. Assume my router is correctly respecting the reserved addresses. LLIPs aren't going to pass through to the router's outside interface ...
1
vote
1answer
162 views

Why did Netflix choose to use CIDR blocks of 100.64.0.0/10 as its private network IP space?

Netflix gave a public tech-talk explaining their network, and one specific design puzzled me. See Page 25 at this talk (Netflix's Migration into VPC), they seemed to choose to use 100.64.0.0/10 as ...
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votes
3answers
131 views

How to tell which one is the source IP and MAC address of the data being received?

I have to work with an FPGA module already running a code written by someone else. I have no access to the FPGA code. Now the setup is something like this:- FPGA is connected to the pc via ethernet ...
1
vote
1answer
76 views

What format is "1.34.128.0/113'?

I know of two format that use similar notation, Classless Inter Domain Routing (CIDR) and Variable Length Subnet Mask (VLSM). However the numbers after the / is usually less than 32. However in this ...
4
votes
3answers
550 views

Does Cell Phone use Public or Private IP address? [closed]

Does mobile phone/cell phone get a private IP address or public IP address? If the cell phone gets a private IP address, I assume that the telecom operator uses carrier grade Network Address ...
6
votes
1answer
298 views

Why is an IPv6 Link-Local Address a /10?

I'm currently studying for my CompTIA Network+ Exam and am a bit confused as to why the IPv6 link-local address is a /10 and not a /12 or /16. Since each character in an IPv6 address is 4-bits and ...
0
votes
1answer
60 views

Is it possible to append custom data to every packet of a request? [closed]

For an end-to-site VPN, i.e. where a device (VPN client) is responsible for encapsulating the GRE packet, is it possible to send some custom data along with the GRE packet beyond just the standard ...
2
votes
2answers
58 views

Before the invention of Classless Inter-Domain Routing (CIDR) did hosts have subnet masks assigned?

Before the invention of CIDR, did hosts also have a subnet mask assigned or only have an IP address and the network was determined by the class of the IP address?
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1answer
96 views

Which MAC should be used: device MAC or Interface MAC?

My L3 switch has ~30 interfaces. If you look at the output below there are two MAC addresses showing in the results of the show interface command. The hardware address is the same for all interfaces. ...
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2answers
76 views

Identify IP of the client causing high interface usage on uplink port

Background: We are observing a high interface load (spikes up to 1G) on a WAN (dedicated link) uplink port of a Cisco switch. How can we find the IP of the client that is causing this high load? I ...
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2answers
36 views

When neigbour solicitation and router solicitation are used to get the IPv6 address, then what is the role of 0:0:0:0:0:0:0:0/128?

I am learning computer networks, but getting confused each time I proceed my analysis. Kindly help. Thanks in advance!
6
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3answers
772 views

Why couldn't a nework address be used as as broadcast address as well?

I am taking a refresher on Networking and I found out that: Network address is an IP address with all 0s after the subnet mask Broadcast address is an IP address with all 1s after the subnet mask ...
2
votes
1answer
66 views

IP address that can not be reached from outside of device

I am sorry if this is a silly question, but I am developing an application that should connect to itself over sockets, but to make it secure it should only be reachable from local device. I believe I ...
3
votes
1answer
72 views

VLSM Determining Switch IP

i was given a network 130.4.0.0/16 that i needed to use vlsm on. which i did and got these vaules: Address | Mask| Assignable Range | Broadcast 130.4.0.0 | /22 | 130.4.0.1 - 130.4.3.254 | ...
3
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2answers
93 views

Does each router have the IP addresses of all the routers and hosts connected to the 'Internet'?

I am new to computer networking,and was reading about the topic routing. According to my understanding,each router has a routing table associated with it. From that table it could know,which output ...
6
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2answers
1k views

Is it true that the fd00::/8 address range (ULA) in ipv6 is for machines that you NEVER want to speak with anything on the Internet?

Is it true that the fd00::/8 address space (User Local Addresses) in ipv6 is for machines that you NEVER want to speak with anything on the Internet? I was just reading that here and rather surprised ...
2
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1answer
96 views

Working Out A Router IP Address

i am in my first semester of networking, in my exam i got completely derailed when i was asked to find the router ip address. i was given the following information about the network: VLANS: ...
5
votes
1answer
142 views

Class A most significant bits '0' as in RFC1166 or older or '00' as suggested in RFC4632?

I was just reading RFC4632 "2. History and Problem Description" and I don't get the part about Class A with MSB '00'. That would in my understanding mean, there are actually only 64 available networks,...
5
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2answers
177 views

IP Address starting with 253

I have no idea if this is the right place to ask this question, I'm very sorry if it isn't I have here data containing an IP address that starts with 253.45.xxx.xxx But I've looked up everywhere and ...
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2answers
119 views

Does the same IP cause IP conflict if one is from /22 other is from /24?

I have two hosts. They both have the same IP/subnet, ex.: 1.2.3.4/24 on both. I know this is bad, since there will be duplicate IP in the network. OK. But: If I have different (?) ranges: 1.2.3.4/...