Data Communication Reviewer

Reviewer informationCom Chapter 1-5 Chapter 1 Intranet- qualified group on a company and only in allows internal employee gate. Extranet- grammatical case of communicate that allows outside vendors special admission charge to limited info in a company. protocols- Rules of communication. * An identified mouther and manslayer * An agreed-upon method of communicating * frequent language and grammar * Confirmation or acknowledgement requirements Elements of a mesh topology * Rules or agreements protocols or how the heart and soul is semt, straight offed, authentic and interpreted. * Massages units of info that travels Medium means of inter colligateing these devices, on a lower floorside trans larboard the messages* Devices devices on the engagement exchange messages meanings- a generic enclosure that encompasses forms of communication enabled by the Internet. Devices- several devices work to see that the message is by rights directed to the obtain to the refineme nt device. Icons- symbols that graphically pre directs lucre devices and media. * Desktop reckoner * Laptop * Server a computer dedicated to providing app services * IP Phone a digital phone* local argona profits media * Wireless media LAN switch around common device for interconnect LANs * Firewall provides security to meshings * Router helps direct messages amidst communicates * Wireless way of lifer * Cloud summarize a group of networking devices * pale media IP (Internet Protocal) & TCP (Transmission Control Protocol) just slightly common protocols * WWW HTTP * email SMTP * Instant messae XMPP * IP telephony SIP Convergence coming together of technologies onto a digital platform. It occurs when computer communications all use the equivalent rules to transport their messages. Network Architecture the conceptual plans on which a sensual network is built. Fault tolerance- needs to function even if some components expose * Scalability- networks ability t o grow & react to future changes * choice of service- performance level of services. Prioritize traffic and its characteristics to manage info. * and Security Packets-single message is broken into small blocks of information. Bandwidth- measure of the data-carrying capacity of the network. Chapter 2 Elements of communication * Message source, or sender * Destination, or receiver *Channel- media that provides pathway Network- refers to data networks carrying massages. Segmentation- all messages are broken into smaller pieces Multiplexing- occurs when segments of two messages back tooth shuffle into to each one other(a) and share the medium. * Increased efficiency of network communication block off device- a piece of equipment that is either the source or the destination of a message on a network. Host- an end device that sends or receives messages. Clients- other multitudes that set up to store and share info by the horde servers *The host address is a unique sensual addres s apply by hosts inside a LAN. Intermediary device- connects the somebody host to the network and connect multiple individual network to form an internetwork. Network entre devices* Internetwork devices * Communication severs * Modems * Security devices Network media Copper, Fiber-optic cable, Wireless Encoding- refers to the way data is converted to patterns of electrical, light, or electromagnetic energy. LAN- a group of end devices and substance abusers under the inhibit of a common administrator. WAN- a network that is used to connect LANs that are geographically far apart. Internetwork- is a collection of two or more than LANs connected by WANs. Proprietary A limited-use protocol owned by a company. Network Representations Network interface card (NIC)- provides the physical connection to the network at the PC or other host device. * Physical port- is a connector or outlet on a networking device where the media is connected to a host.* Interface- refers to how the device c an allow 2 different networks to communicate. The organizations that standardize networking protocols are * IEEE Institute of Electrical and Electronics Engineers * IETF Internet engineering Task Force Interaction of Protocols * Hypertext guide Protocol (HTTP) common protocol that governs the way that a web server and a web guest interact. displace protocol Transmission Control Protocol (TCP) is the transport protocol that manages the individual conversations between web servers and web clients. * Internetwork protocol * Network access protocols describes 2 primary functions Data-Link Management & the physical transmission of data on the media. Layered Models describe the complex deal of network communication. Open Systems interconnectedness (OSI) is the most widely known internetwork reference model.Provides an abstract description of the network communication process. Developed by International Organization for Standardization (ISO). Application, Representation, Session, Transport, Network, Data Link, Physical TCP/IP Model defines the 4 communication functions that protocols perform. * Application, Transport, Internet, Network Access Encapsulation- Process of adding control info as it passes through the work model Decapsulation- process of removing extra information Protocol Data social unit (PDU) generic term for data at each level. Chapter 3 institution Layer has 3 primary functions * Coding and conversion of application layer data * Compression of the data * Encryption of the data TCP/IP protocols Domain Name System (DNS) used to resolve internet names to IP address. * HTTP used to delight files that make up the web pages of the WWW. * unsubdivided Mail Transfer Protocol (SMTP) used for the transfer of mail messages and attachments. * Telnet a terminal emulation protocol used to provide remote access to servers and networking devices. * File Transfer Protocol (FTP) used for interactive file transfer between systems. Process each e xecuting program loaded on a device. Client/server model Deamon are describes as auditory modality for a request from a client. Application layer services and protocolsPeer-to-peer networking and applications * 2 or more computers are connected through a network and can share resources such as printers and files without having a dedicated server. nslookup a utility that allows the user to manually query the name servers to resolve a given host name. ipconfig/displaydns displays all the cached DNS entries 3 common message types are * GET- is a client request for data. * POST and PUT- are used to send messages to that upload data to the web browser. E-Mail Server Processes * Mail Transfer actor (MTA) process used to forward e-mail. * Mail Delivery Agent (MDA)Server Message Block (SMB) a client/server file-sharing protocol. Chapter 4 Transport Layer provides transparent transfer of data between end users, providing unquestionable data transfer services to the upper layers. It enables applications on devices to communicate. * Tracking the individual communications * Segmenting data and managing each piece * Reassembling the segments * Identifying the different applications * Performing accrue control between end users * Enabling error recovery * Initiating a session Flow Control can prevent the loss of segments on the network and avoid the need for retransmission.Used to avoid buffer overflows. Two most common transport layer TCP (Transmission Control Protocol) incurs additional command processing overhead time to gain functions. * Web browsers, E-mail, File transfers UDP (User Datagram Protocol) provide the basic functions for efficiently delivering the data pieces. Has the advantage of providing low-overhead data delivery. * DNS, Video streaming, Voice over IP (VoIP) 3 basic operations of reliability * Tracking shiftted data * Acknowledging received data * Retransmitting any unacknowledged data Socket refers only to the unique crew of IP address and port modus operandi.Internet Assigned Numbers Authority (IANA) assigns port number. Different types of ports * Well-known ports (0 to 1023) reserved for services and applications. * Registered ports (1024 to 49151) are assigned to user processes or applications. * Dynamic or private ports (49152 to 65535) also known as ephemeral ports, are usually assigned dynamically to client applications. netstat a command that is an important network utility that you can use to support TCP connections. It lists the protocol in use, the local address and port number Datagram is a UDP segment (piece).Flags are six 1-bit fields contain control information used to manage the TCP processes * URG Urgent pointer field significant * ACK Acknowledgement field significant * PSH Push function * RST reset the connection * SYN Synchronize sequence numbers * FIN No more data from sender *flags have fields that the only value is 1 bit and, therefore, has only two values 1 or 0. 3 way handshake mensuration 1 SYN, Step 2 SYN and ACK, Step 3 ACK. Expectational acknowledgement occurs when TCP uses the acknowledgement number in segments sent back to the source to indicate the next byte in this session that the receiver expects to receive.Window size is the amount of data that a source can transmit before an acknowledgement must(prenominal) be received. Chapter 5 OSI Layer 3 provides services to exchange the individual pieces of data over the network between identified end devices. The network layer describes four tasks to be performed * Addressing software systems with an IP address * Encapsulation is the process of adding that information. * Routing is the process router perform when receiving packets * Decapsulation is the process of removing encapsulation data at different layers. Source IP address is the IP address of the displace hostDestination IP address is the IP address of the receiving host. IP header contains the address information and some other bi ts that identify the PDU as a network layer PDU. Packet is referred when an OSI layer 4 PDU has been encapsulated at the network layer. skip over is each route that a packet takes to reach the next device. general network protocol * IPv4 most widely used network protocol. * IPv6 currently in use in some area. * Novell IPX a widely ordinary internetworking protocol in the 1980s and 19990s. * AppleTalk Apple Computers correctitude networking protocol. Connectionless Network Service (CLNS) a protocol used in telecom network. IPv4 basic characteristics * Connectionless * Best effort (unreliable) * Media independent *Some networks have media restrictions and must enforce a Maximum Transmission Unit (MTU). Fragmentation is the process when the network layer builds the packets according to specification. Key fields * IP source addressing * IP destination addressing * Time to Live (TTL) * Type of Service (ToS) * Protocol * Flag and Fragment Offset Other Key Fields * interpret ation * Internet head Length (IHL) * Packet Length * Identification Header Checksum * Options * Padding *Because broadcast do not travel beyond the network boundary, the network is known as a broadcast domain. admittance router is the router a network uses to send and receive messages beyond the network. Hierarchical addressing is read from the most general information to the most specific. Subnetting the process when a large network needs to be divided into smaller subnets, additional network codes can be created using some of the bits designated for the host. *The default route is used when the destination network is not represented by any other route in the routing table.Next hop is the address of the device that will process the packet next. *The route info can be manually configured on the router, creating what is known as a static route. Dynamic routing when routers learn about routes automatically from other routers in the same internetwork. Routing Protocols are the set of rules by which routers dynamically share their routing information. * Routing Information Protocol (RIP) * Enhanced Interior Gateway Protocol (EIGRP) * Open Shortest Path First (OSPF) 3 key factors to aim when grouping hosts into a common network * Purpose * Ownership * geographical location