X Stream - Computer Communication and Networks - Case Study Example

Computer Communication & Networks January 16 Network and Protocol Process that occur in the network when you access the X stream server. X-Stream Server Table OF Contents Introduction ………………………………………... Page 2-3 X-Stream Server ………………………………………… Page 3-8 Conclusion …………………………………………… Page 8 References ……………………………………………. Page 9 Introduction Internet has revolutionized the way we communicate, learn, collaborate and share. In order to enable technological advancements, including semantic web, web 2.0 and social networking, online learning, interactive and collaborative educational forums, websites, online shopping, a technological layer serves as a foundation behind the scenes. However, the fundamentals of these layers are the same that enables a communication channel from one end of the planet to the other. As X stream is one of the recent technological educational portals that facilitate tutors and students to collaborate and exchange information, we will discuss the insights of this portal by demonstrating the necessary methods, protocol techniques and processes. However, in order to give a better idea, we have to take TCP/IP protocol suite in to account. Moreover, the foundation for this technological layer that enables a communication channel for internet applications is the IP addresses itself. The priority of the IP is vital because the rest of the TCP/IP protocol suite is fabricated on the IP. However, a recently introduced modification for improving the efficiency of IPv4 32 bit addressing is the CIDS (Classless Inter-Domain Routing) (Linton 2011). Likewise, IP address is assigned a job for developing and constructing the data packets in the same standardized method along with packet management associated with data transmission between interlinked devices in an efficient way. The primary objective is to establish a path for data packets to travel and serve as a basis for delivering network based online applications and services via a TCP/IP suit. The purpose is to expand accessibility of these web-based applications globally and provide services to users such as sharing and uploading documents, pictures, videos, electronic email, video conferencing, chatting, forums, social networks etc. in a broad spectrum, a common platform is now established that is empowered with the mentioned services to make communication valuable. Consequently, for educational communication, a student portal named as X stream has been established, that will serve as a common platform for all the students and tutors, professors and staff for the same university or college. However, apart from some common examples of web enabled services above, the X stream provides advanced services bundled with customization options for students to gain insights on their studies effectively. The report will follow a thorough discussion of the semantics behind these services ranging from a home user establishing remote connectivity to an X stream server. X-Stream Server The first component that is the fundamental part of accessing Internet is connectivity. However, in order to establish connectivity, an Internet connection is required and an Ethernet with workable drivers is required within the system. However, in order to check the connectivity, just type the following syntax in the command prompt i.e. Ping (space) (destination address) for example ping www.yahoo.com. Moreover, for tracing the route of the connection can also be executed via command prompt by typing the syntax tracert (space) (Destination address). Similarly, this command displays the hops of each router in the way for establishing a connection between the source and destination. However, other protocols and devices are also involved for establishing and transmitting error free transmission in a shortest period of time. After sustaining Internet connectivity, the second component of interest is the Ethernet adapter. The Ethernet adapter must be bind with certain values, the first most important is the IP address following with Gateway, Subnet Mask and DNS servers. It is considered to be the most popular Local Area Network technology that is implemented globally (Ethernet. 2007). In order to establish a wired connectivity, a twisted pair cable needs to be connected to the Ethernet adapter and the other end must be connected to a home based DSL router + switch. These home based DSL routers have now built-in switch and wireless connectivity as well. However, a home user must have an Internet subscription from the Internet Service Provider (ISP). After discussing the connectivity on the physical layer, now we will discuss the mechanisms that take place on the other layers of the TCP/IP model. A characteristic Ethernet frame is constructed on six constraints i.e. Preamble, destination address, Source address, type, data and CRC. The description of each of these constraints is defined as: The primary job of this constraint is to synchronize the clock rates of data packets for the source and destination. Likewise, the address is six bytes in length, which is liable to categorize and identify frames for the source and destination address. The layer that is utilized for communication of this constraint is the network layer. In case of an unmatched frame, the frame is rejected. Type is another constraint that handles IP addresses available on the higher layer protocol. However, there are situations where this constraint incorporates protocols from Apple talk, Novell NetWare etc. Finally, CRC the last constraint is responsible for error checking, correction and control. In case of a corrupt, incomplete or damaged packet, it is dropped to sustain an acceptable connectivity. As more than one request can be at the same path or the same network segment for the X stream server, Collision Detection Multiple Access with Collision Detection CSMA/CD can best solve this issue. Computer desktop encyclopedia has published a comprehensive definition of CSMA/CS stated as “The LAN access method used in Ethernet. When a device wants to gain access to the network, it checks to see if the network is quiet (senses the carrier). If it is not, it waits a random amount of time before retrying. If the network is quiet and two devices access the line at exactly the same time, their signals collide. When the collision is detected, they both back off and each wait a random amount of time before retrying”. The request for accessing an X stream server generates from the home user computer and reaches on its way to a DSL Router/ switch. Switches are intelligent devices that maintain MAC address of the source and destination. The information is stored in a database known as the Management information base (MIB). The fields that are available in a typical MIB include MAC address, Interface type and Time to live (TTL). The MIB provides value to the network by establishing communication between nodes efficiently. Consequently, network congestion is minimized, and unnecessary traffic is eliminated from the network making it resilient and productive. Likewise, the process of communication between nodes is carried out by querying MAC address. The query is performed by a command known as Address Resolution Protocol ARP. Reverse ARP is also used in some cases. The functionality of ARP includes a broadcast message to each node available on the network to identify and match the MAC address of the destination so that connectivity can be established. However, each computer on the network represents a different MAC address. After the match of the MAC is found, the connection is established. The MAC address is usually comprises of Organizational Unique Identifier (OUI) and an assigned value from a specific vendor. The size of a Mac address ranges to 48 bits in size and the OUI holds the manufacturer data comprises of hexadecimal values. These vendor assigned values are customized for different purpose. We will discuss IPv4 in this scenario, as there are no special instructions for IPv6, the IPv4 address is constructed on 4 octets i.e. 8bit each x 4 = 32 bits. For example, an IP address representing 10.1.1.2 is a 32 bit network address with all octets filled. As mentioned before, the Ethernet must be configured with an IP address, Gateway, Subnet Mask and a DNS to establish connectivity on the Wide area network. The X stream server is on a remote location and requires Wide area network connectivity to establish connection. Likewise, the home user will initiate a connection request via an IP address. The IP address will use the home network gateway and subnet mask to push the request forward to the home DSL router. The first hop of this request from the home user network is the router. Routers are intellectual devices that are responsible to transmit data or connection to the destination address or network. Moreover, the work of a router is hectic, as it is connected to different WAN interfaces/ networks to relay the traffic to the required network. After receiving the request, the routers responds and relay the request to the requested network i.e. the ISP Router. However, the data packet is received at the router end do not have the actual IP address of the X stream server, at this point, MAC addresses of source and destination and IP addresses of source and destination in to the packet header are available. The home user identifies the router by learning the MAC address on interface A. The router, after identifying the home user connection request, relays the request to a different network based on a different subnet via interface B. At this point, the router learns both MAC address i.e. the source and the destination. Lastly, the request is terminated at the destination network i.e. the X stream server at a remote location. This explanation is limited to Ethernet, Switches and Routers. Now we will move one step further to get more insight of this process by considering the TCP/IP model consisting of Physical layer, Data link layer, network layer, Transport layer and Application layer (Ross 2009). The application layer will allow a home user to enter a Uniform Resource Locator (URL) for entering the address of the X stream server online portal. As mentioned earlier, the request will travel through the Ethernet card to the Home DSL router. Accordingly, the home DSL router will route the connection request to another router on the first hop. If the home user is trying to access the X stream server from an ISP, the configuration of the first hop router will redirect the request to the university network as per the ISP configuration. If we assume that the home user network is configured with a C class IP address with subnet i.e. 192.168.0.56/32 at Interface A. likewise, these settings are configured on the home DSL router, as it is a possibility of using Network Address Translation for configuring private IP addresses on more than one system. Moreover, global IP addresses are limited and require more security and administration. NAT provides security and is a built in feature in DSL modems requiring less administration. As per network dictionary it is defined as a methodology via IP addresses are mapped and encapsulated from one group to another. Moreover, it is configured when there is a requirement of configuring internal IP addresses that cannot be used on the external network due to privacy or compatibility issues (Network Address Translation. 2007). Likewise, interface sense the destination and relays the request to the ISP router. The ISP router will be configured on a different subnet for example, 168.58.0.0/28 (ISP network). The ISP router than relays the connection request to the university router on the send hop. However, the DNS address of the X stream server will be fetched by the ISP’s DNS servers, as there is a requirement of translating the URL in to IP addresses (DNS server. 2011). The university router configured on a subnet of 65.22.100.0/32 (University Network) configured on Interface C, receives the request and redirects it to the destination i.e. the X stream server located within the premises of the university. Likewise, the DNS request travels through the home user DSL router to the ISP router. The datagram from the home user interface is routed to the ISP’s network via routing protocols including OSPF, BGP and RIP. These protocols deliver the request from the home user to the router where routing tables are created and IP address of the X stream server website i.e. www.x-stream.com from the DNS is fetched. However, in order to query HTTP, TCP sockets are opened from the web server by the user via TCP SYN segment which is a 3 way handshake and this is the first step. Secondly, web server gives a response in terms of TCP SYNACK and the connection establishes. Similarly, TCP sockets accept HTTP request containing the IP datagram that is router to www.x-stream.com (Seth, Venkatesulu, 2008). Therefore, the X stream server answers the HTTP request by opening the requested web page or service. Conclusion The journey from a home based DSL connection to the destination server hosted at a remote location was interesting. We have learned the modification of data packet headers and their transmission from each network device provides a great picture. In summary, we have illustrated connectivity from home to the destination server by incorporating routing commands, TCP/IP model, routing commands, DNS functionality, communication of routers via different subnets and Network address translation for breaking global IP addresses into local IP addresses. Furthermore, we have also mentioned routing protocols including Opening shortest Path first (OSPF), Routing Information Protocols (RIP) and Border Gateway Protocols for explaining remote connection. References LINTON, S., 2011. Ip V 6: the Next Internet Protocol. Global Conference on Business & Finance Proceedings, 6(2), pp. 73-78. Csma/cd. 2011. Computer Desktop Encyclopedia, , pp. 1. ROSS, K.W., 2009. Computer networking: a top-down approach Pearson/Addison Wesley. Network Address Translation. 2007. Network Dictionary, , pp. 334-334. SETH, S. and VENKATESULU, M.A., TCP/IP architecture, design and implementation in Linux Hoboken, New Jersey : Wiley ; c2008. Read More