Define protocol, Computer Network Security

For simplicity, each character is regarded as one data packet, which means that the data in each packet should have the max length of only 1 byte.

Your own packet header (not the UDP header) is needed to maintain the order of data packets. There will be no obligation on the format of headers, and you can design it in any way you like. For example, you can add a 32-bit sequence number ahead of the data you want to send.

The ACK packet is similar to the data packet except that it only has the header and does not have any data in it.

1925_sequence number.png

Figure: GBN Packet Header Example

 Buffer

Each node should have a sending buffer. All data packets (not ACK) should be put into the buffer before sending, and removed from the buffer once the corresponding ACK is received. The sending buffer should be long enough to avoid the conflict of packet numbers given the window size below. If the buffer is full, the sending function simply waits until more space is available.

 Window

The window moves along the sending buffer. If you implement the buffer as an array, the window should move back to the beginning of the array after reaching the end. Packets in the window should be sent out immediately. The size for the window will be passed in as an argument when starting your program.

 Timer

There is only one timer for GBN protocol. It starts after the first packet in the window is sent out, and stops when the ACK for the first packet in the window is received. After the window moves, if the first packet of the new window has already been sent out, the timer should simply restart, otherwise it should stop and wait for the first packet.

The timeout for the timer should be 500ms and all the packets in the window should be resent after timeout.

Posted Date: 2/20/2013 4:13:15 AM | Location : United States







Related Discussions:- Define protocol, Assignment Help, Ask Question on Define protocol, Get Answer, Expert's Help, Define protocol Discussions

Write discussion on Define protocol
Your posts are moderated
Related Questions
FRAGMENTATION AND PATH MTU IPv6 source is responsible for fragmentation. Routers simply drop datagrams bigger than network MTU. So source have to fragment datagram to arrive d

Ask question #Minimum.. 100 words accepted#

Q. Attacks on wireless network WSN are vulnerable to attacks which compromise the integrity of the WSN nodes by decreasing the nodes' fault tolerance capabilities, data distrib

Question: (a) Which type of attacker represents the most likely and most damaging risk to your network? (b) What is the basic reason that social engineering attacks succeed?

Network Virtual Terminal It is a set of principles describing a very simple virtual terminal interaction. The NVT is needed in the start of a Telnet session. Communication wit

Risk Control Strategies Once the ranked vulnerability risk worksheet has created, they should choose one of following 4 strategies to control each risk: •    Apply safeguards wh

I have an assignment of Computer Security to submit. Will you guys help me making my assignment???

1.  We used the National Vulnerability Database. Select a recent vulnerability from that Database and analyse it from the following aspects: Criticality level Impact in

Mapping between a hardware address and a protocol address is known Address Resolution. A router or host uses address resolution when it requires to transmit a packet to another dev

Gateways They transfer packets among network machines that have different protocols (e.g. between a WAN and a LAN). They access a packet formatted for one protocol and change