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Questions tagged [ip-address]

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

20
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6answers
5k views

What stops someone from configuring their network with IP addresses they do not own?

Here's the scenario. I was picturing a university that bought a range of IP addresses. I think they'd still be inside a ISP (right?), but they'd have freedom to configure stuff the way they wanted. ...
0
votes
1answer
33 views

IPv6 variables or other methods of shortening

From the dawn of when I heard about IPv6 many years ago, to my continued hesitance to make good use of it in today's world where it's eventually going to become necessary... my biggest issue I think ...
11
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8answers
5k views

Why are IP addresses given to each interface and not device? What would the implications of that be?

Why do we need to give IP addresses to each interface? Wouldn't giving one to each device be enough?
-1
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1answer
33 views

Find Major network vslm

Im a bit lost with this question. In order to get proceed with the vslm i need to find the Major network of this subnet 121.118.40.0 /19. For me the major network is 121.118.32.0/19, but when I run ...
1
vote
1answer
37 views

Finding the network address for given host IP?

Answer provides the procedure to find the network address when a packet with destination IP(198.51.100.223/21) is reached at a router. But a network packet has the destination IP 198.51.100.223 in ...
-1
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0answers
27 views

ip overlapping conficting [duplicate]

123.45.0./16 i have to divide it in two rooms something like this room 1 will have 256 IP addresses and room 2 will have 512 IP addresses what i have done is this F1/0 : 123.45.0.1 255.255.255....
1
vote
1answer
71 views

Urgent: how to configure different interface using same ip subnet in asa 5506?

Scenario is in old asa firewall 5505 I have switch port access vlan command in different interface. Just like below: interface Ethernet0/0 ! interface Ethernet0/1 switchport access vlan 2 ! ...
0
votes
1answer
78 views

IP Addressing-Why All zero(0) and all one(1) in subnet id bits are reserved?

I'm studying about class less inter domain routing. I've come to know that all zeros(0) in host id bits refers to subnet address and all ones(1) in host id bits refers to broad cast address. So, ...
0
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1answer
14 views

Daisy chaining IOT devices without switches? [closed]

I have multiple IoT board with two network interface in each device. I want to connect them in a daisy chain without help of switch. The eth1 of first device will be connected to eth0 of second device,...
7
votes
1answer
230 views

Is the first address of the subnet a valid configurable address in case of IPv4 and IPv6 point to point networks?

Am I correct, that first address of the subnet is a valid addresses to configure in hosts/routers in case of IPv4 and IPv6 point to point networks? For example, in case of 192.0.2.0/31 one of the ...
0
votes
1answer
38 views

What happen if broadcast is made to first and last address of other network?

Broadcast to network id What happens if you broadcast to the first IP of another network ? broadcast to broadcast id of another network What happens if you broadcast to the last IP of another ...
1
vote
1answer
28 views

I am trying to set up aDHCP server in a VLAN for practical of networking with Linux

I am a Linux user requesting advice about setting up a DHCP with a VLAN based on offices on one floor for the practical purpose. Is this good enough for implementing a VLAN structure with a DHCP ...
0
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1answer
68 views

It's not showing the DNS why it is called reverse IP lookup?

I have searched a lot but I didn't get the reason that even after giving the IP address it never shows the DNS. If it doesn't give the DNS then why it is said to be reverse IP lookup?
1
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1answer
55 views

What's the relationship of a Router with its loopback interface in logic?

I have a Router1 with a loopback 0 connected to the Router2: the interface brief is bellow: Router1>show ip interface brief Interface IP-Address OK? Method Status ...
0
votes
1answer
81 views

(CISCO Packet Tracer) Overlap Error

I am trying to set up a network of for different organisational departments based on a given typology: Using Cisco 2911 routers & 2960-24TT Switches. With given addressing of: 'EIGRP 101' 172....
2
votes
1answer
51 views

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 ...
4
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2answers
65 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 ...
9
votes
1answer
718 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
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2answers
130 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 ...
1
vote
0answers
49 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....
1
vote
3answers
84 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
votes
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,...
-1
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1answer
51 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
609 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 ...
5
votes
3answers
206 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
44 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 ...
0
votes
1answer
31 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 ...
0
votes
1answer
175 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
votes
1answer
224 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 ...
-1
votes
3answers
81 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
vote
1answer
53 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
34 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 ...
1
vote
2answers
55 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 ...
1
vote
1answer
822 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
1k 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
0
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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
433 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
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1answer
69 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" ...
1
vote
1answer
129 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 ...
3
votes
2answers
122 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
votes
1answer
180 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 ...
2
votes
1answer
292 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 ...
3
votes
3answers
186 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
79 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
984 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
457 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
63 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 ...
3
votes
2answers
64 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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2answers
127 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. ...
1
vote
2answers
79 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 ...