Questions tagged [ip]
For questions about Internet Protocol (IP), an OSI layer-3 network protocol. There are two current IP versions in use: IPv4 and IPv6.
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Share a network that has a static ip [closed]
So i have a LAN cable that comes from a switch then I plugged it in to my pc then i entered my static ip, subnet mask and default gateway on my ipv4 setting and I get internet connection on my pc. Now ...
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Does the MSS (Maximum Segment Size) prevent IP Fragmentation in all cases?
I have read that the MSS (Maximum Segment Size) is used to prevent IP Fragmentation.
Now if the two communicating devices exist on the same network, and this network have a MTU (Maximum Transmission ...
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What does "direct-attached networks" mean?
This page says the following:
TCP controls this maximum size, known as Maximum Segment Size (MSS),
for each TCP connection. For direct-attached networks, TCP computes
the MSS by using the MTU size of ...
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Can you send data in LAN without an IP?
From What I know, IPs are used to communicate b/w two different networks say LAN1 and LAN2... and MACs are used to communicate within a LAN.. I think this because my instructor says that Hubs and ...
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Does the IP header have a "Padding" field?
I found two images of the IP header, one image shows a field called "Padding", while the other image don't show the "Padding" field:
Which one of these two images is correct?
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Tcp/Ip to OSI model [duplicate]
The universal standard of communication using the TCP/IP is this:
Now comparing it to the OSI model,can we conclude that the Internet layer is the Network layer in the OSI model and the Link layer is ...
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Why we need MAC address when transferring if we have static IP? [duplicate]
I just wanted to know if h1 and h2 have static ip and we want to transfer some file, so why we need to use mac address? Are not static ip addresses enough for this ?
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Packet tracer help with routing between multiple company routers with vlans and wireless routers
Im still quite a novice to packet tracer (so im sorry if this has been answered) and I'm trying to ping both vlans at company1 router to both Lans at company2 router but for some reason when the ...
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How CIDR helped to slow down routing table growth?
Besides allowing for a greater number of ip addressed, Classless Interdomain Routing (CIDR) was also intended to slowdown routing table growth in core routers.[1] I may understand how it expands the ...
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Relation between the BACnet 4 layers and the TCP/IP 5 layers
How are the BACnet 4 layers (physical, data link, network, application),
related to the TCP/IP 5 layers (physical, data link, network, transport, application)?
Are they separate of them, or build on ...
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IP packet expired by TTL generate an ICMP response in any case?
Acording to Wikipedia IPv4 article for TTL header field:
An eight-bit time to live field limits a datagram's lifetime to
prevent network failure in the event of a routing loop. It is
specified in ...
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What is the difference between a private IP and a MAC address? [duplicate]
I am taking a course preparing me for the Network+ certification. I wanted to know what the purpose of a private IP is when a MAC address exists. From what I understand, the MAC address is used to ...
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How are we still able to use IPv4 address even with NAT? [duplicate]
My question is why haven't we run out of IPv4 public IP as well because now almost all home has a router which is assigned a public IP. Is it possible to have multiple layers of NAT on the router-ISP ...
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How lsp-ping works with php in picture?
If my understanding is correct, lsp-ping will have destination IP addresses set to loopback address(127.0.0.x), to force the label switching of the packet and thus checking the LSP connectivity.
When ...
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Loops in routers-same packet?
Considering a loop topology between a few routers with a host connected to one of them, when it's default routing directs to the cycle.
Even when observing Wireshark, how can we know its the same ...
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Constraint on length of message & segment to be integral number of bytes, as mentioned in Cerf & Kahn's Paper
I have a question about the below excerpt from Cerf, V.; Kahn, R. (1974). "A Protocol for Packet Network Intercommunication". IEEE Transactions on Communications. 22 (5): 637–648.
... ...
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How many /56's are there in a /49 IPv6 [duplicate]
I am studying subnetting in IPv6.
I came across the following question from a website called Subnetting Practice, which I will quote below.
How many /56s are there in a /49?
Could someone please ...
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What should we do if the number of bytes to be transferred are not in multiples of eight in ipv4? [duplicate]
(it is take from book called special edition tcp ip, pic taken for better formatting and ease to read)
Theory that I am trying to understand-:
So i found a question that is relevant to this-:
->a ...
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43
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Simple IPv6 Global Unicast question
I was reading this article which states:
RFC 3587 states that out of the 128 bits in IPv6 addresses, left most
three bits are must be fixed as 001. Remaining 45 bits are reserved
for global routing ...
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How is 65535 bytes is total length of IP datagram?
The maximum size of an IPv4 packet is 65,535 because the Total Length field is a 16-bit unsigned integer, which has a possible 65,536 values (from 0 to 65,535).
This created 2 confusions for me.
Say ...
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How to use IP pool
I am just beginner, I just want to setup my mini data center and for testing i get a FTTH connection and /30 ip pool, ISP reply is something like that, "IP Pool 103.15.xx.xx/30 has been assigned ...
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What are the IP/MAC addresses of requests between 2 different subnets? [closed]
Assume that networks 172.15.10.0/24 and 172.15.11.0/24 are connected through a router with interfaces 172.15.10.254 (MAC3) and 172.15.11.253 (MAC4).
If host A sends a packet through its network ...
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2
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Why shortened version of IP4 exists and it is undocumented but supported everywhere?
For example there is an IP address 192.168.0.1
It is clear that you can use it as the full line, but try that one 192.168.1
It will also work, and it will be automatically converted to 192.168.0.1
...
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DHCP Discover Broadcast and its IP (255.255.255) [duplicate]
Cheers, I am trying to learn more about DHCP, and when studying about the session that DHCP goes through every one mentions that it broadcasts a discover message at IP: (255.255.255.255) (as seen here ...
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Why is this 254.63.0.1, not a valid host address?
Getting the below error, when trying to configure the ip address 254.63.0.1 as an SVI.
Switch(config)#interface vlan 254
Switch(config-if)#ip address 254.63.0.1 255.255.0.0
Not a valid host address -...
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3
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Why the host part of a Mask is 254 (256-2) instead of 253?
Don't hate me for being such a newbie but I'm so confused. If we have 32 bits, each octet adds up to 255, why the host part is 254 (in a 255.255.255.0 mask) instead of 255 - 2 ?
Thanks so much for ...
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How IP packet's payload bigger than the whole former PDU (segment)? [duplicate]
As far as I know:
File is too big ---> Fourth layer (TCP or UDP) divide it to a multiple segments ---> Then each segment encapsulated separately into a packet.
What means if I have 10 segments, ...
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How does a computer determine that an Ethernet frame contains an IP packet? [duplicate]
So far as I can tell, there is no "Next Protocol" ID at the Ethernet / data link layer.
Nor do IP packets seem to contain any magic numbers for identification purposes.
Does the OS bind each ...
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Dividing network into subnets [duplicate]
My teacher uploaded this example question and solution as explanation of the topic:
I watched some videos about it but none of them made it fully clear, what I don't understand here is:
What are ...
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146
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Inherent flaw in stateless firewalls?
I am but a lowly (software) developer dabbling with setting up a network in AWS and am having trouble understanding the fundamentals of stateless firewalls, or Network ACLs as they're also referred to ...
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How are IP broadcasts handled at lower levels
When I use a broadcast IP address, for example 198.255.255.255, what will happen when it gets passed down to the link-layer which will then look for the corresponding MAC address in your ARP table. ...
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Custom option in IP header
I would like to add (or piggyback on an existing not used) a custom option to the IP header. I've full control of the IP stack at both end points, but I've no control on all the hops in the route (...
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why ip adresses are divided into network portion and host portion when we already have NAT [duplicate]
I don't understand why ip adresses are divided into network portion and host portion? is the host portion really necessary when we already have NAT?
for example, if ip addresses only have network ...
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point-to-point at IP layer
I was reading one of 5G standards specifying signalling transport https://www.etsi.org/deliver/etsi_ts/138400_138499/138472/15.06.00_60/ts_138472v150600p.pdf and noticed (section 6):
The IP layer of ...
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Is there any benefit of combining several unicast into a single multicast?
If a node has to send the same data to multiple nodes, it is obvious that multicasting the data would improve bandwidth usage. However, if a node has to send different data to different nodes, would ...
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How does a host use its default gateway? [duplicate]
Each host has its own default gateway and uses that to send packets outside of its network. But in each packet, there is only 1 header field for the destination IP address. So, how can that host send ...
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Cisco Packet Tracer gives "Invalid IP Address" when I assign an address to a router [duplicate]
I was given an exercise where I have an IP address range and I have to configure multiple sub networks from that range. The address is 238.61.192.128 with the mask 255.255.255.128 (/25). I created my ...
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If current IP ranges for PCS are in conflict with a new systems network, how do you re-IP the PCs and the Servers?
I have a question about IP conflicts. Let's say you have a company building full of PCs on a network. Then a firm buys out that company and institutes its new system and new network for that building. ...
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What does an IP Address with CIDR represent precisely?
This question is more a question of definition then a technical one:
You have some network with the network identifier 172.16.0.8 and a subnet mask 255.255.255.248 (/29)
We know that the usable ...
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Routing traffic within the subnet - How to decide CIDR range?
I am following this tutorial to configure multiple subnets and firewall:
https://networkfirewall.workshop.aws/setup/distributedmodel.html
This tutorial shows how to filter traffic through the ...
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Identify vrf within packet capture
I have a scenario where i am capturing data where mutiple customers vrfs traverse
I am looking at my capture and ofcourse i see source & destination
However, these addresses could come from ...
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If IPv6 exists, why do we still pay for static IPv4 addresses?
Given that there is some ridiculous number of IPv6 addresses per every single person on the planet, why do ISPs still charge for IPv4 addresses? Why not just give the user an IPv6 address?
Is it ...
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What does it mean to “plumb” an IP address?
Plumbing an IP address means what? What are some examples of it?
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What defines a device as connected to the Internet? [closed]
I recently saw a SO question: Are there global networks other than the Internet? I am aware of other networks such as ATM and the telephone network, which are not part of the Internet. My question is, ...
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2
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Why in the TCP/IP model the link & physical are one?
I'm currently learning about the OSI model and the TCP/IP models, and I was wondering: Why in the TCP/IP model the physical layer and the data link layer are combined?
I'll state how I understand the ...
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Why router can't be used for converting different model of network but gateway can do this?
We know that Router can't be used for converting different model (e.g OSI model to TCP/IP or TCP/IP model to OSI) of network. It isn't a multiprotocol converter. But gateway is a highly sophisticated ...
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What is SLIP good for? [closed]
I read a bit about SLIP in few places, and from what I understand, the goal of this protocol is to allow the transfer (or encapsulation) of IP packets between hosts over a serial line.
But I don't ...
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lan with multiple ip [duplicate]
If imagine lan assigned ip from from this range (192.168.1.0/24) then can we assign another ip from same subnet mask? If no why?
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Why can IPv4 and IPv6 use strict source routing(in options field) and flow label respectively inspite of connectionless protocol?
In IPv4 option field one field option is source routing option this means packet will always be routed by router Or not. Packet can also be routed by source such routing is known as source routing. ...
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How is IP address assigned to physical location
I was thinking about buying IP addresses so i could setup small hosting company. I know that i can rent IP addresses aswell. I have alot of knowledge about networking in common but i don't understand ...
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