1. Protocol-Independent Multicast (PIM) [4]:
Protocol Independent multicast [4] is defined as the collection of multicast routing protocols that are used to route multicast IP traffic to different distribution points over LAN, WAN and the Internet. PIM is classified into two different versions and operates in two different modes PIM-SP (sparse mode) and PIM-DM (dense mode) [7] that are used to perform routing operations similar to that of other routing protocols like OSPF, BGP and so on. The properties of PIM are as follows [7]
• It provides a loop-free tree communication between two routers.
• It is termed as protocol independent as it does not advertise the topology information to build the loop free tree in networks.
PIM-Dense Mode [8]:
The dense mode uses a flood and prune method [4] in which the network is flooded with multicast traffic and the unwanted traffic, the routers with no hosts and the unused links are pruned. This mode is suitable only for small-scale networks due to traffic flooding. PIM uses source distribution tree for building the network. The process occurs as follows in dense mode [7].
• The PIM neighbors are discovered in the network by using 224.0.0.13 (PIM) on the attached links.
• The multicast traffic is flooded in the network and the unwanted traffic is pruned in the network.
• The multicast table is maintained by updating the network using graft, assert and state refresh.
PIM-Sparse Mode [8]:
The sparse mode uses a pull and explicit join method [8]. There is no traffic flooding unless it has been requested in the network. This method is scalable on large networks and is considered to be a better and efficient method than the dense mode. Sparse mode uses source-based tree or a shared tree based on th...
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...co, IP Multicast Technology Overview: http://www.cisco.com/en/US/docs/ios/solutions_docs/ip_multicast/White_papers/mcst_ovr.html#wp1008981 [3] Hedlund, Brad, Identifying Ethernet Multicast: http://bradhedlund.com/2007/11/21/identifying-ethernet-multicast/ [4] Network technologies, PIM Overview: http://network-technologies.metaswitch.com/multicast/what-is-pim.aspx [5] Official Cisco Press Reviewer, Multicast – Understand How IP Multicast Works: http://www.firewall.cx/networking-topics/general-networking/107-network-multicast.html [6] Solie, Karl CCIE Practical Studies, Volume II: http://www.informit.com/library/content.aspx?b=CCIE_Practical_Studies_II&seqNum=28 [7] Virigina Cs Itlab, Chapter 10: IP Multicast: http://www.cs.virginia.edu/~itlab/book/pdf/Ch10_v1.pdf [8] Wikipedia: Protocol Independent Multicast:
http://en.wikipedia.org/wiki/Protocol_Independent_Multicast
Localization-free routing protocols: the protocol does not require the full-dimensional location information, all it need is the depth information of each node. The most popular routing protocol in this class is Depth-Based Routing (DBR) [1] protocol. (section 4)
FEATURES NEW TO ICMPv6........................................4 Neighbor Discovery …......................................................... 5 Anycast Address …............................................................. 6
Lab 1 demonstrates the capabilities of congestion control algorithms implemented by Transmission Control Protocol (TCP). It provides three scenarios to simulate these algorithms and will later compare the results.
The graph shows comparison of the three scenarios for sent segment sequence number. The green curve represents No_Drop scenario where it shoots up as it is a perfect scenario where there is no loss of packets. Whereas the blue curve which representd Drop_Fast Scenario increases exponentially because there is loss of packets and retransmission takes place.
The attacker forwards only specific packets to next node, it generally chooses which kind of packet to forward. These attacks are effective if the attacker is in the path of the data flow. The attacker may choose to act as a black hole and just absorb the packet but then some nodes may declare it as failed. The assumption in multihop network is the trust relation among participating nodes about forwarding packets. Selective forwarding can also be caused by jamming or collision (physical or link layer) of a node outside the data flow.
With an IPv4 network, all the work consisting of network renumbering and assigning of new address schemes would had been done manually. Another useful feature of IPv6 is the multi-homing technique. It allows simultaneous connections which are established to two ISPs. Compared to IPv4, IPv6 has a much simpler packet header structure, which is designed to minimize the time and efforts that go in to header processing. IPv6 offers better end-to-end connectivity than its predecessor IPv4. The most exciting applications to emerge in todays world is peer-to-peer applications such as multi-player online games, video-conferencing (streaming), file sharing and
...a flood of packets. Therefore, the victim node or sometimes the whole network can get easily paralyzed [24].
Sending data through the internet efficiently has always posed many problems. The two major technologies used, Ethernet and Asynchronous Transfer Mode (ATM), have done an admirable job of porting data, voice and video from one point to another. However, they both fall short in differing areas; neither has been able to present the "complete" package to become the single, dominant player in the internet market. They both have dominant areas they cover. Ethernet has dominated the LAN side, while ATM covers the WAN (backbone). This paper will compare the two technologies and determine which has a hand-up in the data trafficking world.
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.
Building a star topology is much more expensive and time consuming than the bus network. The increased costs come in the form of cabling and the central device(s). However, star topologies can be easily expanded to accommodate more nodes and troubleshooting is much easier because connectivity problems are simpler to isolate than a bus network.
Networks in organisation are dynamic and complex entities which can be quite challenging to configure and manage. (Kim & Feamster 2013). These corporate networks consist of multiple routers, switches, firewalls, middleboxes and a particular advantage of network management is the ability to monitor the entire business network. As all the devices are interconnected with many event occurring simultaneously, problems with once device can eventually lead and spread throughout...
4. A. Crespo and H. Garcia-Molina. Routing indices for peer-to-peer systems. In Proc. of the 28th International Conference on Distributed Computing Systems, July 2002.
The TCP/IP is the most important internet operation protocol in the world. While IP protocol performs the mass of the functions which is needed for the internet to work. It does not have many capabilities which are essential and needed by applications. In TCP/IP model these tasks are performed by a pair of protocols that operate at the transport layer. The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP). These two protocols are vital when it comes to delivering and managing the communication of numerous applications. To pass on data streams to the proper applications the Transport layer must identify the target application. First, to be able to attain this, Transport layer assigns an application an identifier. In the TCP/IP model call this identifier a port number. Every individual software process needing to access the network is assigned a un...
... middle of paper ... ... TCP/IP operates at levels 3 and 4 of the OSI model.