Saturday, February 13, 2010
Friday, February 12, 2010
PROTOCOLS
9P : Plan 9 from Bell Labs distributed file system protocol
AFP : Qaisar Javeed
APPC : Advanced Program-to-Program Communication
AMQP : Advanced Message Queuing Protocol
BitTorrent
Atom Publishing Protocol
BOOTP : Bootstrap Protocol
CFDP : Coherent File Distribution Protocol
DDS : Data Distribution Service
DHCP : Dynamic Host Configuration Protocol
DeviceNet
DNS : Domain Name System (Service) Protocol
eDonkey
ENRP : Endpoint Handlespace Redundancy Protocol
FastTrack (KaZaa, Grokster, iMesh)
Finger : User Information Protocol
Freenet
FTAM : File Transfer Access and Management
FTP : File Transfer Protocol
Gopher : Gopher protocol
HL7 : Health Level Seven
HTTP : HyperText Transfer Protocol
H.323 : Packet-Based Multimedia Communications System
IMAP : IMAP4, Internet Message Access Protocol (version 4)
IRCP : Internet Relay Chat Protocol
Kademlia
LDAP : Lightweight Directory Access Protocol
LPD : Line Printer Daemon Protocol
MIME (S-MIME): Multipurpose Internet Mail Extensions and Secure MIME
Modbus
Netconf
NFS : Network File System
NIS : Network Information Service
NNTP : Network News Transfer Protocol
NTCIP : National Transportation Communications for Intelligent Transportation System Protocol
NTP : Network Time Protocol
OSCAR : AOL Instant Messenger Protocol
PNRP : Peer Name Resolution Protocol
POP : POP3, Post Office Protocol (version 3)
RDP : Remote Desktop Protocol
Rlogin : Remote Login in UNIX Systems
RPC : Remote Procedure Call
RTP : Real-time Transport Protocol
RTPS : Real Time Publish Subscribe
RTSP : Real Time Streaming Protocol
SAP : Session Announcement Protocol
SDP : Session Description Protocol
SIP : Session Initiation Protocol
SLP : Service Location Protocol
SMB : Server Message Block
SMTP : Simple Mail Transfer Protocol
SNMP : Simple Network Management Protocol
SNTP : Simple Network Time Protocol
SPTP : Secure Parallel Transfer Protocol
SSH : Secure Shell
SSMS : Secure SMS Messaging Protocol
TCAP : Transaction Capabilities Application Part
TDS : Tabular Data Stream
TELNET : Terminal Emulation Protocol of TCP/IP
TFTP : Trivial File Transfer Protocol
TSP : Time Stamp Protocol
VTP : Virtual Terminal Protocol
Waka : an HTTP replacement protocol
Whois (and RWhois) : Remote Directory Access Protocol
WebDAV
X.400 : Message Handling Service Protocol
X.500 : Directory Access Protocol (DAP)
XMPP : Extensible Messaging and Presence Protocol
Sunday, February 7, 2010
WHY OSI MODEL STARTED??
The idea behind the creation of networking standards is to define widely-accepted ways of setting up networks and connecting them together. The OSI Reference Model represented an early attempt to get all of the various hardware and software manufacturers to agree on a framework for developing various networking technologies
In the late 1970s, two projects began independently, with the same goal: to define a unifying standard for the architecture of networking systems. One was administered by the International Organization for Standardization (ISO), while the other was undertaken by the International Telegraph and Telephone Consultative Committee, or CCITT(the abbreviation is from the French version of the name). These two international standard bodies each developed a document that defined similar networking models.
In 1983, these two documents were merged together to form a standard called The Basic Reference Model for Open Systems Interconnection. That's a mouthful, so the standard is usually referred to as the Open Systems Interconnection Reference Model, the OSI Reference Model, or even just the OSI Model. It was published in 1984 by both the ISO, as standard ISO 7498, and the renamed CCITT (now called the Telecommunications Standardization Sector of the International Telecommunication Union or ITU-T) as standard X.200.
| OSI Model | ||||
|---|---|---|---|---|
| Data unit | Layer | Function | ||
| Host layers | Data | 7. Application | Network process to application | |
| 6. Presentation | Data representation and encryption | |||
| 5. Session | Interhost communication | |||
| Segment | 4. Transport | End-to-end connections and reliability | ||
| Media layers | Packet | 3. Network | Path determination andlogical addressing | |
| Frame | 2. Data Link | Physical addressing | ||
| Bit | 1. Physical | Media, signal and binary transmission | ||
APPLE TALK
| OSI Model | Corresponding AppleTalk layers |
|---|---|
| Application | Apple Filing Protocol (AFP) |
| Presentation | Apple Filing Protocol (AFP) |
| Session | Zone Information Protocol (ZIP) AppleTalk Session Protocol (ASP) AppleTalk Data Stream Protocol (ADSP) |
| Transport | AppleTalk Transaction Protocol (ATP) AppleTalk Echo Protocol (AEP) Name Binding Protocol (NBP) Routing Table Maintenance Protocol (RTMP) |
| Network | Datagram Delivery Protocol (DDP) |
| Data link | EtherTalk Link Access Protocol (ELAP) LocalTalk Link Access Protocol (LLAP) TokenTalk Link Access Protocol (TLAP) Fiber Distributed Data Interface (FDDI) |
| Physical | LocalTalk driver Ethernet driver Token Ring driver FDDI driver |
The AppleTalk design rigorously followed the OSI model of protocol layering. Unlike most of the early LAN systems, AppleTalk was not built using the archetypal Xerox XNS system. The intended target was not Ethernet, and it did not have 48-bit addresses to route. Nevertheless, many portions of the AppleTalk system have direct analogs in XNS.
One key differentiation for AppleTalk was it contained three protocols aimed at making the system completely self-configuring. The AppleTalk address resolution protocol (AARP) allowed AppleTalk hosts to automatically generate their own network addresses, and the Name Binding Protocol (NBP) was dynamic system for mapping network addresses to user-readable names. Although systems similar to AARP existed in other systems, Banyan VINES for instance, nothing like NBP has existed until recently.
Both AARP and NBP had defined ways to allow "controller" devices to override the default mechanisms. The concept was to allow routers to provide the information or "hardwire" the system to known addresses and names. On larger networks where AARP could cause problems as new nodes searched for free addresses, the addition of a router could reduce "chattiness." Together AARP and NBP made AppleTalk an easy-to-use networking system. New machines were added to the network by plugging them and optionally giving them a name. The NBP lists were examined and displayed by a program known as the Chooser which would display a list of machines on the local network, divided into classes such as file-servers and printers.
DYNAMIC DNS
DNS? What's that???.........
HERE'S ANSWER::-
You got to this Web page by looking up http://www.sahilarora.org/dynamic/. DNS, the Domain Name Service, is responsible for the big part in the middle: www.sahilarora.org. The Internet is divided into literally millions of domains; each one has its own name.To a human, names like that (or ibm.com, or yahoo.com, or any of the other four million domain names registered) make perfect sense. IP addresses consist of four numbers, each between 0 and 255. More or less. (Some blocks of numbers are reserved for a variety of special purposes.) But not to the computer.
The computer doesn't have a clue. Computers work with numbers. Computers use IP addresses ("dotted quad" numbers like 10.20.30.255) to talk with each other on the Internet.
DNS is the middleman, translating domain names into numbers (and, occasionally, the other way around).
There's only so many numbers out there, at least as far as the computer is concerned. (Basically, each of the four parts in the "dotted quad" address can only be between 0 and 255.) Silly technical limitations eat up a lot of those addresses; historical design decisions eat up some more; and of course a LOT of them are already in use.
This means that Internet IP addresses are a finite, scarce resource, and have to be treated somewhat carefully.
EXAMPLE::=
Suppose you have a normal, $20 per month, Internet dialup account from "Some Local ISP, Inc." They have three thousand customers, but it's rare that all of them are online at the same time. (In fact, if they follow industry practice, they probably only have 500 or so phone lines anyway.) So that ISP may only have 600 or 700 IP addresses -- enough to provide one for each phone line, a few for internal use, a few for future growth, but nowhere near one for each of those 3000 customers.
Or maybe you have a cable modem, though "Big CableCo Inc." Whenever your cable modem goes online (when you first plug it in and turn it on), it broadcasts a request for an open address, and some computer in their office eventually answers. Cable modem addresses are usually assigned with "leases," which work just like the lease on an apartment - you're guaranteed to have that address for a certain time, but after that all bets are off. Your landlord (the cable company) might evict you, forcing you to move (get a new IP address) at the end of the lease. (These 'leases' usually only last for a few days, and sometimes only a few hours.) At the end of the lease, you may be able to negotiate a new lease, but you can't be sure of it.
So not everyone can have their own IP address. Your ISP, cable company, or whoever, might let you have a dedicated IP, but they'll probably charge you extra for it. It's more likely, though, that they can't or won't help you...
FUNCTION:::-
Dynamic DNS providers provide a software client program that automates the discovery and registration of client's public IP addresses. The client program is executed on a computer or device in the private network. It connects to the service provider's systems and causes those systems to link the discovered public IP address of the home network with a hostname in the domain name system. Depending on the provider, the hostname is registered within a domain owned by the provider or the customer's own domain name. These services canfunction by a number of mechanisms This group of services is commonly also referred to by the term Dynamic DNS, although it is not the standards-based DNS Update method. However, the latter might be involved in the providers systems.
