Unicast packets are sent from host to host. The communication is from a single host to another single host. There is one device transmitting a message destined for one reciever.
Broadcast
Broadcast is when a single device is transmitting a message to all other devices in a given address range. This broadcast could reach all hosts on the subnet, all subnets, or all hosts on all subnets. Broadcast packets have the host (and/or subnet) portion of the address set to all ones. By design, most modern routers will block IP broadcast traffic and restrict it to the local subnet.
Multicast
Multicast is a special protocol for use with IP. Multicast enables a single device to communicate with a specific set of hosts, not defined by any standard IP address and mask combination. This allows for communication that resembles a conference call. Anyone from anywhere can join the conference, and everyone at the conference hears what the speaker has to say. The speaker's message isn't broadcasted everywhere, but only to those in the conference call itself. A special set of addresses is used for multicast communication.
Function OSI 7 Layer
- OSI layer 2
- The data link layer of the OSI model, responsible for logical link control, and media access control.
- The network layer of the OSI model, responsible for routing, flow control, segmentation, error detection and error correction.
- The transport layer of the OSI model, responsible for transparent transfer of data for a connection, including sequencing, retransmission, flow controland stream control.
- The session layer of the OSI model, (typically ignored in Internet protocols) providing full or half duplex checkpointing, adjournment, termination andrestart procedures.
- The theoretical presentation layer of the OSI model, (typically handled by other levels in Internet protocols) responsible for delivery and formatting ofmessages, e.g. encryption/decryption, codeset conversions (ASCII to EBCDIC) or other abstraction manipulations.
- The application layer of the OSI model, responsible for common application services to application processes, e.g. the Mozilla HTML engine used by FireFox and Internet Explorer 4, or the SMTP protocol used by e-mail programs.
Protocol
- RIP
The Routing Information Protocol (RIP) is a dynamic routing protocol used in local and wide area networks.- BGP
The Border Gateway Protocol (BGP) is the core routing protocol of the Internet. It maintains a table of IP networks or 'prefixes' which designate network reachability among autonomous systems (AS).
- DHCP
The Dynamic Host Configuration Protocol (DHCP) is a computer networking protocol used by hosts (DHCP clients) to retrieve IP address assignments and other configuration information.
- DNS
The Domain Name System (DNS) is a hierarchical naming system for computers, services, or any resource connected to the Internet or a private network.
- FTP
File Transfer Protocol (FTP) is a standard network protocol used to copy a file from one host to another over a TCP/IP-based network, such as the Internet.
- GPRS
GPRS Tunnelling Protocol (GTP) is a group of IP-based communications protocols used to carry General Packet Radio Service (GPRS) within GSM andUMTS networks.
- HTTP
The Hypertext Transfer Protocol (HTTP) is an Application Layer protocol for distributed, collaborative, hypermedia information systems.
- IMAP
The Internet Message Access Protocol (IMAP) is one of the two most prevalent Internet standard protocols for e-mail retrieval, the other being the Post Office Protocol (POP).[1] Virtually all modern e-mail clients and mail servers support both protocols as a means of transferring e-mail messages from a server.
- TCP
The Transmission Control Protocol (TCP) is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite (the other being Internet Protocol, or IP), so the entire suite is commonly referred to as TCP/IP.
- UDP
he User Datagram Protocol (UDP) is one of the core members of the Internet Protocol Suite, the set of network protocols used for the Internet. With UDP, computer applications can send messages, in this case referred to as datagrams, to other hosts on an Internet Protocol (IP) network without requiring prior communications to set up special transmission channels or data paths. UDP is sometimes called the Universal Datagram Protocol. The protocol was designed by David P. Reed in 1980 and formally defined in RFC 768.[1]
- OSPF
Open Shortest Path First (OSPF) is a dynamic routing protocol for use in Internet Protocol (IP) networks.Specifically, it is a link-state routing protocol and falls into the group of interior gateway protocols, operating within a single autonomous system (AS).
- ARP
The Address Resolution Protocol (ARP) is a computer networking protocol for determining a network host's link layer or hardware address when only its Internet Layer (IP) or Network Layer address is known. This function is critical in local area networking as well as for routing internetworking traffic across gateways (routers) based on IP addresses when the next-hop router must be determined. ARP was defined by RFC 826 in 1982.[1] It is Internet Standard STD 37.
- EIGRP
EIGRP (Enhanced Interior Gateway Routing Protocol) is a network protocol that lets routers exchange information more efficiently than with earlier network protocols. EIGRP evolved from IGRP (Interior Gateway Routing Protocol) and routers using either EIGRP and IGRP can interoperate because the metric (criteria used for selecting a route) used with one protocol can be translated into the metrics of the other protocol. EIGRP can be used not only for Internet Protocol (IP) networks but also forAppleTalk and Novell NetWare networks.
- RIPV2
RIPv2 is the newer, enhanced version of the RIP routing protocol, and is specified in RFC 1723. In many ways, this newer version is still very similar to its predecessor – it is still a distance vector protocol that uses hop count as its metric (the hop count limit is still 15), and still has a default administrative distance of 120. However, version 2 also introduces a number of features not found in the original version. Firstly, RIPv2 is classless; this means that it can be used on networks that employ variable-length subnet masking (VLSM). This is possible because RIPv2 includes the subnet mask associated with a destination network in its routing table updates. Where routing table updates were broadcast in RIP version 1, RIPv2 instead uses multicasts to send updates – specifically, a router will send updates to the multicast address 224.0.0.9.
