Showing posts with label Protocol. Show all posts
Showing posts with label Protocol. Show all posts

Monday, 5 January 2015

Difference between HTTP and HTTPS


Parameter
HTTP
HTTPS
Acronym for
Hypertext Transfer Protocol
Hypertext Transfer Protocol Secure
Description
It is the request response based application protocol in client-server model & is designed to work within the framework of Internet Protocol Suit.
It is a Secured version of HTTP to allow secure transactions. E.g. Net banking. It wraps the entire communication within SSL, thus, encryption starts before any data is sent.
Ports Used
This Protocol works on TCP/IP Port No. 80 or 8080
This Protocol Uses TCP/IP Port No.443 for data communication.
Encryption
This Protocol is a stateless protocol and do not uses any encryption method.
HTTPS uses long term public and secret keys to exchange a short term session key to encrypt data flow between client and server.

Wednesday, 24 July 2013

SPX (Sequential Packet Exchange) Protocols


It is the version of Novels’ Sequenced Packet Protocol (SPP). It is a transport layer protocol and is used by client server applications. This protocol provides a packet delivery system for third party applications.
Figure given below illustrate the structure of SPX packet.

Connection Control Flag
DataStream Type
Source Connection ID
Destination Connection ID
Sequence Number
Acknowledge Number
Allocation Number
0-534 bytes of data


Connection Control Flag: Four flags are used to control bidirectional data flow of SPX connection. If its value is 1 flag is said to be set and if its value is 0 it is said to not set. Following are four flags:

Thursday, 4 July 2013

Internetwork Packet Exchange (IPX)

Internetwork Packet Exchange (IPX) is a connectionless datagram protocol that is used by the Novell NetWare Operating System.  This protocol is the implementation of Xerox Network Systems’ IDP (Internet Datagram Protocols). It is Layer 3 protocol i.e. Network Layer Protocol.

IPX Protocol is very similar to the IP protocol. Some useful points about this protocol are as follows:
1)Unique 32 bit address is assigned to Logical Networks ranging from 0x1 to 0xFFFFFFFF (Hexadecimal).
2)48 bit node address is used by hosts, which is by default set to network card’s MAC address. Node address and network address are jointly used to identify the host on network.
3)00:00:00:00 means current network.
4)FF: FF: FF: FF is used as broadcast address.
Figure Given below Illustrates the IPX Packet.

Cheksum : Its value is set to FFFFH

Sunday, 31 March 2013

OSI Model

Open System Interconnection is a standard that describes how message  is transmitted and received between two points in telecommunication.It is developed by ISO( International Organization for Standardization ). It is a seven layer model and are labeled 1 to 7 with layer 1 at bottom(as per X.200 Recommendations).This concept of a seven-layer model was provided by the work of Charles Bachman, Honeywell Information Services.Idea behind this model was that the telecommunication between two points can be divided into layers with each layer adding its own set of special, related functions. The seven Layers are: 1)Physical Layer 2)Data Link Layer 3)Network Layer 4)Transport Layer 5)Session Layer 6)Presentation Layer 7)Application Layer. these seven layers are divided into two groups. The upper four layers are used whenever a message passes from or to a user(known as Host Layers). The lower three layers (up to the network layer) are used when any message passes through the host computer(known as Media Layers) . Messages intended for this computer pass

Tuesday, 26 March 2013

File Transfer Protocol(FTP)

File Transfer Protocol(FTP) is Networking Protocol that is used to transfer files from one host to another host based on TCP/IP Network.It Completely works on client server model and make use of separate data and control lines between server and client.User Requires username and password to connect or it may connect anonymously if  server is configured to do so.FTP is not able to encrypt its traffic; all transmissions are in clear text, and usernames, passwords, commands and data can be easily read by anyone able to perform packet capture.
This Protocol is totally transaction oriented.A transaction is defined to be an entity of information communicated between cooperating processes.Transaction has three fields:
1)72 bit Descriptor Field
2)Variable Length Data Field(Including Zero)
3)Variable length Filler Field
Hence,Transaction Length=(72 + data + filler) bits.

<Code> :This field has three 8 bit bytes. The first byte is interpreted as transaction type, the second byte as data type and the third byte as extension of data type.

Transmission Control Protocol(TCP)

Transmission Control Protocol(TCP) is a connection-oriented, end-to-end reliable protocol designed to fit into a layered hierarchy of protocols which support multi-network applications.the primary purpose of the TCP is to provide reliable, securable logical circuit or connection service between pairs of nodes.
following are some functions that are performed by TCP–>
i)Basic Data Transfer:-TCP is responsible to transfer a continuous stream of octets in each direction between its users by packaging some number of octets into segments for transmission through the internet system. TCPs decide when to block and forward data at their own convenience.
ii)Reliability:-The TCP  recovers data that is damaged, lost, duplicated, or delivered out of order by the internet communication system. To do so a sequence number to each octet transmitted, and requiring a positive acknowledgment (ACK) from the receiving TCP. If the ACK is not received within a timeout interval, the data is retransmitted. At the receiver, the sequence numbers are used to correctly order segments that may be received out of order and to eliminate duplicates. Damage is handled by adding a checksum to each segment transmitted, checking it at the receiver, and discarding damaged segments.