The IPv4 address is a 32-bit number that uniquely identifies a network interface on a machine. An IPv4 address is typically written in decimal digits, formatted as four 8-bit fields that are separated by periods.
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Hello IUT, here we do Q/A process (“I guess”). U1710170
Yes, you can type your Q/A in this area
If we want to make a supernet among all students of Inha University how it`s possible? If we know their MAC-address and each one will have Global Static-IP, is there a possibility to make such a supernet. Assume we use classless and we know submasks of all IPs.
Supernetting is required when you want to combine two or more networks into one large network. This is basically used in classful addressing when we have fixed size of block.
Assuming the entire address space of IUT is divided into several subnetworks. Now you are willing to combine some group of private IPs into a Supernet, the simplest way is to write the network ID of all combining network in binary and define the mask by considering only the common sequence of bits which are same in all.
Hi, Kamoliddin.
First of all, you can’t do that. Because, we have limited size of Global IPv4 addresses.
Secondly, any internet provider can not you provide such amount of free ipv4 addresses, because each country has limited size of blogs of ips. This is the reason why we use DHCP (auto-configuration) and we always see different global ip addresses.
Assume we have 2 identical IP addresses in 2 different masks. How we can get the correct destination address?
Same IP with two different mask represent that the IP belongs to different network. To find the destination address for each network corresponding to the given IP, perform the AND operation of IP address with differnt mask. You may relate this scenario with the first IP of the first subnetwork and first IP of the entire network address space. Both IP are same but have different mask.
Hello Professor , i have a question about IP-Address that is personal , can we hide IP address from any outside forces ?
Two simple ways to hide your IP address are using a proxy server or using a virtual private network (VPN).
Hello professor. Should we always update IPv4 header’s checksum field? (U1610199)
I think it may be. if the router changes the header of IPv4, it needs to consider a new value for the checksum, if I am not mistaken. If it isn’t, other devices receiving the packet think that it is damaged.
Hi, Salokhiddin.
I think,Since the router changes the IPv4 header (it decrements the TTL), it needs to calculate a new value for the checksum, otherwise subsequent devices receiving the packet will think it is damaged.
This only applies to IPv4. IPv6 has eliminated the checksum, instead it relies on protocols above and below it to do any error checking.
Hello professor. Should we always update IPv4 header’s checksum field? (U1610199)
Hello everyone, I have a question about number of address available in class A. in class A 255*255*255 adresses are available or there are some default ip adresses ?
Class A has 16 777 216 (2^24) addresses per network and
total addresses in class is: 2 147 483 648 (2^31)
Hello, As we assumed in classful IP we divided IP to classes. Class A has half of all IP which is 2^31. So if you what count host IPs you should subtract 2 for first and last IPs which wouldn`t be gain for use.
Is address aggregation the same as supernetting?
Technically, sometimes both appear different in the context they are used but logically both are same.
Aggregation is basically an IP address minimization process in which large address space is represented as smaller continuous range.
Supernetting combines several small networks into large network (large address space). Both will help in reducing routing table entries and able to represent entire address space into hierarchical distribution of address.
Professor, how do we do attendance ???
Hello there) I have a question. So if 5 computers connected with 1 host hierarchy connection. if I install app for host, will all 5 computer take this app to their OS and may they modify it?
Hope I choose the right topic for this queston)
Helo, actually yes, but it depends, we have consider the OS also. the resource permission should be opened for outside clients using chmod 777 in linux or bit flags in windows
best Regards,
What should be the flag value to indicate the last fragment?
U1710230
it should be 0, and you can know that it is last fragment if the flag is 0
The Flag field in the IP header is used to control and identify the fragments. It contains three bits: reserved, don’t fragment and more fragments. If the more fragments bit is 0, it means that the fragment is the last fragment.
it is 0, because the Flag field in the IP header is used to control and identify the fragments. It contains three bits: reserved, don’t fragment and more fragments. If the more fragments bit is 0, it means that the fragment is the last fragment.
If the value in protocol field is 17, what is the transport layer protocol used is UDP?
If the value in protocol field is 17. What is the transport layer protocol used?
UDP. Because the protocol field enables the demultiplexing feature so that the IP protocol can be used to carry payloads of more than one protocol type.
What is IPv4/IPv6 Dual Stack?
ISPs have chosen an IP address transition method called dual stack. With the dual stack solution, every networking device, server, switch, router and firewall in an ISP’s network will be configured with both IPv4 and IPv6 connectivity capabilities. Most importantly, dual stack technology allows ISPs to process IPv4 and IPv6 data traffic simultaneously.
What does this mean to you? You’ll be able to keep surfing the Internet without wondering if your connection will stop working because of the IP address conversion.
What is the lover limit for data segment of Ethernet fragment?