Nt1310 Unit 7 Data And Communication Methods

1. Message Encoding involves converting the information the host wishes to send into the appropriate medium for transmission. Messages sent across networks are converted down into bits by the sending host and then encoded into a pattern of sounds, light waves, or electrical impulses, depending on the network medium over which the bits are being transmitted.
2. Sending a message is much like a letter in that it is put inside another message that contains the source and destination addresses. If these are not correct the message cannot be sent. This process of putting one message format within another message format is called encapsulation. On the destination end, De-encapsulation will occur when the recipient will reverse the process by
extracting the contained message. The container message is referred to as a frame.
3.
Message timing involves several rules of engagement. Access Method determines when two hosts can know when to begin sending messages and how to respond when errors occur. Flow control is used to manage how much data and the speed at which the data is transferred, allowing source and destination hosts to negotiate correct timing for successful communication. Hosts on the network also have defined Response Timeout rules specifying how long to wait for responses and what action to take if a response timeout occurs.
4. Open standards are designed to create a fair market over which no one can take advantage over or monopolize. These standards are applied across all companies so that all devices are compatible with each other by a minimum standard. This allows a situation such as an OS X computer to access a website run by Linux-based web server. Open standards at the heart encourage interoperability, competition, and innovation, rather than restricted nature of proprietary standards.
5. Default gateways, also known as routers, serve the purpose of allowing message transmission across networks. When an Ethernet frame from a source host is wishing to be sent to a host off network, the source will instead send it to the default gateway, using the router’s MAC address. The default gateway will then forward the message to the intended destination host or the next closest default gateway if still not directly
connected.
6. Addresses can be either physical or logical. The physical address of a host is their MAC address, written in hexadecimal notation. This address is written into the hardware of the host such as in the NIC chip found in many end devices, and is akin to how your mailbox helps set you apart when delivering the message. Conversely, the logical address of a host is their IP address, written in a IPv4 or IPv6. This address varies depending on which network the host is present, as this is what the IP address refers to, much like how your home address is a proper representation of your location amongst an area.
7. As application data is passed down through the tcp/ip process across network media, encapsulation occurs. The form of which a piece of data takes at any stage is referred to as a protocol data unit, or PDU. A PDU will have a different name at each layer to reflect its current functions, following naming conventions according to the TCP/IP suite.