OSPF Packet Types:
The OSPF protocol using its assigned number 89 runs directly over IP. There are five different packet types used by the protocol.
1) Hello: Hello packet is used to discovery and maintain the neighbours in the area.
2) Database Description: Adjacencies are formed using database description packets. The link state advertisements are summarized by the router and passes the information, through database description packets to the adjacent router.
3) Link State Request: After the exchange of the database description packets between router and its neighbour, the router discovers that link state advertisements are required to be updated or complete topological database. Thereby, sending link state request packets to the neighbour in a request for these link state advertisements.
4) Link State Update: Link State Update packet is used to transmit link state advertisements between routers. This could be in response to a link state request packet or to flood a new or more recent link state advertisement.
5) Link State Acknowledgment: The flooding of link state advertisements...
The method of communication over the FCIC II / CJ Net network is the same standard that has been used on the Internet, TCP/IP.
The bitter cold bit against the starved girl’s skeletal body. She was tired. Her parents discussed ways to get to good lands. They told her the only way to have a better life was to sell her into slavery. The girl, only ten years old was silent. She dreamed of fine clothing and good food. The girl went to the House of Hwang. She was too ugly to be in sight; she was kept in the scullery. All dreams of any kind were lashed out of her young mind. Mistreated, beaten, and underestimated, young O-lan learned to work hard and became resigned to her fate. One day, the Old Mistress summoned her and told her that she was to be married to a poor farmer. The other slaves scoffed, but O-lan was grateful for a chance to be free - they married. O-lan vowed to return to the great house one day in fine clothing with a son. Her resolve was strong; no one could say otherwise. Her years of abuse as a slave had made O-lan wise, stoic, and bitter; whether the events of her life strengthened or weakened her is the question.
When using routers, you need many routers in order to route the information to the correct location, as one router will not be able to manage this task. Explain how the routing schemes handle this problem.
OSI – Open Systems Interconnection - is reference model for how applications can communicate over a network. A reference model is a conceptual framework for understanding relationships.
Back in the 1980's, when all music sucked and men dressed like fags, a bunch of sissy Europeans got together in a passionate effort to overstandardize computer networking. They created this thing called the Open Systems Interconnection (OSI) networking suite. Anyone who has taken a CS (Computer Science) or CIS (Computer Information Systems) course knows this; they cram this fact down the student's throat from day freaking one. It is only when the student enters the real world do they realise that the OSI seven layer model is a sham.
TCP/IP is a client/server model. The communication of TCP/IP is point-to-point; each communication is from point in the network to another point. TCP/IP and other applications that use TCP/IP are considered “stateless”. It is “stateless” because each request by the client is unrelated to any previous requests. The network path is freed up because of t...
• Host—Sends and/or receives bundles, but does not forward them. A host can be a source or destination of a bundle transfer. The bundle layers of hosts that operate over long-delay links require persistent storage in which to queue bundles until outbound links are available. Hosts may optionally support c...
The OSI network reference model was developed by the International Organization for Standardization (ISO) to facilitate communication between networks by keeping certain standards open rather than proprietary (Serpanos & Wolf, 2011). Each layer is stacked with the physical layer as the lowest and the application layer as the highest and one can think of each layer as containing stacks of protocols that make network communications function (Serpanos & Wolf, 2011). A protocol is a set of rules written in a common language that allows computers to communicate with each other. Each communication network is a node and the corresponding layer on each node communicates with each other.
An Open Shortest Path First (OSPF) protocol is the most used interior gateway protocol and computation intensive protocol where energy consumption in Internet Protocol (IP) networks is the main concern. The energy in an IP network can be saved by allowing a subset of IP router interfaces on sleep mode setting during the low traffic hours through the model of “move” by dint of an Energy Aware Routing (EAR) strategy, which is completely compatible with OSPF and is based on the “Shortest Path Tree (SPT) exportation” techinque or “Dijkstra's Algorithm”. In case of heavy traffic hours, the EAR strategy is not usable and may cause denial of service. The strategy implemented can help a network operator to control the network performance and allow a smoothed QoS degradation. This performance evaluation study permits to save about 30% of network links with a insignificant rise of link loads and network path lengths.
Spanning tree protocol is a protocol that prevents loops that are not wanted in a network. In order for a network to work properly it has to have only one active path between two network stations. If there are multiple active paths between stations loops can and will occur. When loops occur, there can sometimes be duplicate messages in the network. The loops are created by the network and if the devices that connect the network segments are all configured to forward, they will continuously forward frames into an endless network loop. If there are enough loops going then a frame will not reach its destination. The reason duplicate messages occur is because sometimes switches will see situations appear on both sides of it. When this occurs that is when spanning tree protocol comes in. In order to shut down the loops bridges and switches exchange BPDU messages with other bridges and switches to detect loops and then remove them by shutting down selected bridge interfaces. BPDU is short for bridge protocol data unit. Bridge protocol data units are part of the spanning tree protocol and they help describe and identify the parts of a switch port. The bridge protocol data unit allows switches to obtain information about each other. All the switches gather information from each other by exchanging data messages. In order for them to exchange messages they have to elect a root switch for the topology. The root switch has to be unique. The way they elect they have to have a unique switch for every local area network segment. To exchange messages they have to remove all loops by putting them in a backup state. Now to talk about states there is 5 different states. Two of the five states do not participate in frame forwarding. Frame forwarding is what the three main states do. The three main states are listening, learning, and forwarding. The other 2 are blocking state and disabled state. When you enable the spanning tree protocol the network goes through the blocking state and then the listening state and learning state are enabled after being turned on. If the protocol is properly configured the ports are stabilized to the forwarding or blocking state. The blocking state does not participate in the frame forwarding. It removes frames that are received from the attached segment. It also discards frames from another port for forwarding.
This memorandum will attempt to explain the Open Systems Interconnection Model, known more simply as the OSI Model. The OSI Model has seven levels, and these levels will be discussed in detail. Particular mention will be made to which level TCP/IP functions with the OSI Model.
It just doesn't get much simpler than the physical bus topology when it comes to connecting nodes on a Local Area Network (LAN). The most common implementation of a linear bus topology is IEEE 802.3 Ethernet. All devices in a bus topology are connected to a single cable called the bus, backbone, or ether. The transmission medium has a physical beginning and an end. All connections must be terminated with a resistor to keep data transmissions from being mistaken as network traffic. The terminating resistor must match the impedance of the cable.
Local Area Networks also called LANs have been a major player in industrialization of computers. In the past 20 or so years the worlds industry has be invaded with new computer technology. It has made such an impact on the way we do business that it has become essential with an ever-growing need for improvement. LANs give an employer the ability to share information between computers with a simple relatively inexpensive system of network cards and software. It also lets the user or users share hardware such as Printers and scanners. The speed of access between the computers is lighting fast because the data has a short distance to cover. In most cases a LAN only occupies one or a group of buildings located next to each other. For larger area need there are several other types of networks such as the Internet.
Explain how the two important transport protocols deliver messages on behalf of the application and discuss the differences between them
TCP/IP operates at both levels 3 and 4 of the OSI model. The TCP portion of TCP/IP operates at level 3 (Network) as its primary function is to control the flow of data. IP operates at level 4 (Transport) of the OSI model. IP is the protocol responsible for the actual transmission of packet across the network.