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TCP/IP - Transmission control protocol/Internet protocol
IP:
The main task is to support internetwork addressing and packet forwarding and routing.
Is a connectionless protocol that envelops data passed to it from the transport layer.
TCP:
Is a reliable and connection-oriented protocol, that ensures that packets are delivered to the destination computer.
If a packet is lost during transmission, TCP has the capability to resend it.
Provides reliability and ensures that the packets are delivered.
There is more overhead in TCP packet.
Data - Stream-> Segment -> Datagram -> Frame
UDP:
Is a best-effort and connectionless oriented protocol.
Does not have packet sequencing, flow and congestion control and the destination does not acknowledge every packet it receives.
There is less overhead in UDP packet.
Data - Message -> Packet -> Datagram -> Frame
TCP Handshake:
1. Host sends a SYN packet
2. Receiver answers with a SYN/ACK packet
3. Host sends an ACK packet
IPv4 - Uses 32 bits for its address
IPv6 - Uses 128 bits for its address
LAN media access technologies
Ethernet:
Characteristics: Share media / Uses broadcast and collision domains / Uses carrier sense multiple access with collision detection (CSMA/CD) access method / Supports full-duplex on twisted-pair implementations / Can use coaxial or twisted-pair media / Defined by standard 802.3
10base2 implementation: ThinNet, uses coaxial cable, maxlength 185 meters, provides 10 Mbps.
10base5 implementation: Thicknet, uses coaxial cable, maxlength 500 meters, provides 10 Mbps.
10base-T implementation: Uses twisted-pair wiring, provides 10 Mbps, usually implemented in star topology.
Fast Ethernet implementation: Uses twisted-pair wiring, provides 100 Mbps.
Token ring:
Uses a token-passing technology with a star configured topology.
Each computer is connected to a central hub, MAU - Multistation Access Unit.
Transmits data at 16 Mbps.
Active monitor - Removes frames that are continuously circulating on the network.
Beaconing - If a computer detects a problem with the network, it sends a beacon frame. It generates a failure domain where computers and devices will attempt to reconfigure certain settings to try and work around the detected fault.
FDDI--Fiber Distributed Data Interface:
Is a high speed token-passing media access topology.
Transmits data at 100 Mbps
Provides fault tolerance by providing a second counterrotating fiber ring.
Enables several tokens to be present on the ring at the same time.
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