...TCP/IP - Socket Programming Jim Binkley 1 sockets - overview sockets ◆ simple client - server model ◆ – – – look at tcpclient/tcpserver.c look at udpclient/udpserver.c tcp/udp contrasts “normal” master/slave setup for TCP ◆ inetd on UNIX - mother server ◆ some details - there are more... ◆ Jim Binkley 2 sockets in BSD world since early 80’s, 4.2 BSD ◆ client/server model ◆ “like” unix file i/o up to a point, can be redirected to stdin/stdout/stderr (on unix) ◆ sockets are dominant tcp/ip application API ◆ – – other API is System V TLI (OSI-based) winsock - windows variations on sockets » sockets in windows event-driven framework 3 Jim Binkley sockets ◆ basic definition - “endpoint of communication” allows connected streams (TCP) or discrete messages (UDP) between processes on same machine, cross network ◆ in o.s., really read/write data queues + TCP has connection Queue (server side) ◆ talk to “socket” with handle/sock descriptor ◆ Jim Binkley 4 kinds of sockets acc. to address family; i.e. how does addressing work ◆ IP address family -> IP addr, tcp/udp port ◆ traditional BSD families ◆ – TCP/IP (AF_INET; i.e., Internet) » TCP/UDP/”raw” (talk to IP) – – – Jim Binkley UNIX (intra-machine, pipes) XNS, and even APPLETALK, DECNET, IPX ... 5 sockets client handle read write read write server socket layer r/w queues tcp stack Jim Binkley 6 syscalls - TCP client/simple test server int s =...
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...Checkpoint: TCP/IP LAN Plan 1. An IPv6 address is made up of how many bits? a. 32 b. 48 c. 64 d. 128 e. 256 The answer to this question is d. Ipv6 address has 128 bits which is better than Ipv4 which has only 32 bit addresses. If I understand it with Ipv4 the amount of addresses will soon run out. With Ipv6 as stated in the book unless every star in the universe were assigned an address it is unlikely to run out of addresses. With Ipv4 it was stated that there are only 4 billion possible addresses. With Ipv6 there are 3.4x10^38 or 34 followed by 37 zeroes. Ipv6 resolves some problems found in Ipv4 such as limited addresses, security, sometimes complicated setup and quality of service (QoS). QoS describes the ability of a network to prioritize data packets based on the type of information. Ipv6 makes the handling of special packets easier to implement, such as applications that use video or audio. Whereas Ipv4 uses a dotted decimal in 8 bit sections, Ipv6 uses a hexadecimal format in 16 bit sections. At first I was a bit confused over what this meant and looking at the address example further confused me. Then after further reading I discovered that each 16 bit section was ended with a colon. It was explained that there are three sections to the address they are public topology, a site topology, and an interface identifier. If I am right then the address giving in the book would break down like this: 2001:DB8:0:0:0:2ed3:340:ab The first 3 16 bit sections 2001:DB8:0: represent...
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...ABSTRACT Without TCP/IP, there would be no internet. TCP and IP are two separate data communication and transmission protocols. They are considered the core protocols of TCP/IP network model. The model encompass four layers; application layer, host-to-host transport layer, Internet layer, and network access layer. Each layer process data that it receives and push up and down the model layers according to its intended function. This paper will provide an analysis of the layered protocol structure of TCP/IP networks. Keywords: TCP/IP networks model, application layer, host-to-host transport layer, Internet layer, and network access layer. INTRODUCTION All internet services that we use and rely on in our daily life are based on TCP/IP networks....
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...is on the TCP/IP security. As we have seen the transmission of data as securely as possible has become top on the list for many companies and persons. As we have begun using the Internet more and more to conduct business remotely, we need to ensure that our most sacred data is protected from harm. To ensure that we understand the transmission of data using TCP/IP, I will explain the history of the protocol and the reason for this being the established standard used. As we have read and know it is a combination of two known protocols that were combined to become one. The Transport Control Protocol is used to ensure successful delivery of data. It carries the destination and source information such as the address for both. The IP protocol or Internet Protocol is the second. This protocol is only for sending data. It combined with TCP will ensure that the data is transmitted successfully. When the protocols began to communicate they can use on of many ways to ensure successful communication. One being the hand shake method. There are more than one and will be explained in the paper. With that transmission come the possibility of interference and high jacking of data. One common discussed security hole is the prediction of the send sequence. There is also the SYN and FIN scanning, which each attack. Then there is UDP security concerns, which an attacker uses empty UDP ports to send datagram’s. These are just a few ways there are security holes defined with using TCP/IP and I will...
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...TCP/IP LAN Plan CheckPoint An IPv6 address is 128 bits compared to the IPv4, which is only 32 bits. The subnet mask of an IP address, defines the network portions and which part is the host portion. Each of the three class IP addresses have a range, which cannot be routed across the internet. Since the IP address 172.19.243.254 falls in the range of the class B 172.16 to 172.31 ranges it cannot be routed across the internet. Computers to communicate on a TCP/IP logical network they must have an IP address. An IP address is unique to the devices on a network providing the network ID and the host ID there for, for a computer to talk to another computer within a logical network they both must have an network ID and a host ID. Reallocating bits from the host ID to a network ID one must remember subnets take the power of 2, meaning to create 16 subnets one must reallocate 4 bits to the 2 power (2x2=4x2=8x2=16). A class C network address is 255.255.255.0, leaving the last octet for identification of subnets. 32 subnets equals 6 bits, converted to binary provides a 11111100 binary bit pattern with the sixth 1 representing the 32nds place. The binary bit pattern 11111100 is equal to (128+64+32+16+8+4) 252, which is a subnet mask of 255.255.255.252. To assign address to 62 hosts one must use the formula 2n-2 with n representing the number of host bits. 62 host is (2*2=4*2=8*2=16*2=32*2=64-2=62) 6 host bits. Why subnet, the ability to break up large networks in...
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...1. Three basic building blocks of the internet? = Packet-switch hardware, a communications protocol (TCP/IP), Client/server computing 2. Latency? How does it interfere with internet function? = low level of service quality (delay/late) 3. Explain how packet switching works? = Packet switch is a method slices digital message into packets, routes the packets along different communication paths as they become available, and then reassembles the the packets once they arrive at their destination 4. How is the TCP/LP protocol related to information transfer on the internet? = it is the core combinations protocol for the internet. TCP establishes the connections among sending and receiving web computers and makes sure the packets sent by one computer aww received in the correct sequence by the other, without any packets missing IP provides the addressing scheme and is responsible for the actual delivery of the packet 5. What technological innovation made client/server computing possible? = Client 6. What is cloud computing, how has it impacted the internet? = Cloud computing refers to a model of computing in which firms and individuals obtain computing power and software applications over the internet, rather than purchasing the hardware and software and installing it on their own computers. Cloud computing is the fastest growing form of computing 7. Why are smartphones a disruptive technology? = that radically alters the personal computing and e-commerce landscape ...
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...The Transmission Control Protocol/Internet Protocol (TCP/IP) suite is indisputably one of the most popular networking protocol suites ever developed. TCP/IP is an industry standard designed for large networks consisting of network segments connected by routers, and is the protocol used on the Internet (Hillpot & Ivy, 2005). TCP/IP’s roots can be traced back to research conducted by the United States Department of Defense (DOD) Advanced Research Projects Agency (DARPA) as early as 1960. In the best bureaucratic tradition, DARPAs (or ARPA, as it was called at the time) involvement in the creation of the internet began with a memo dated April 23, 1969 that was authored by Joseph Licklider (Waldrop, 2012). Between1970 to 1996 the Internet evolved, ARPANET hosts started to use Network Control Protocol, a preliminary form of what would become the Transmission Control Protocol (TCP). Than the TCP/IP protocol suite was established which led to the Domain Name System (DNS), ISPs, and the introduction of HTTP. In retrospect, the program that Licklider put together in the early 60’s would evolve into perhaps the most successful federal research program with the greatest significant impact on society in history. The TCP/IP suite maps to a four-layer conceptual model known as the DARPA model, which was named after the U.S. government agency that initially developed it (Waldrop, 2012). Each layer of the DARPA model corresponds to one or more layers of the seven-layer OSI model. The...
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...Question 5 (a) Explain 4 ways in which a firm might increase profit by raising the wage it pay (4mks) (I) Through cutting wages and benefit for employees at the bottom of the corporate ladder by using incentives such as high wage ,performance rewards. (II) Through providing advancement opportunities for entry level as to e nsure the success of the company . (III) Through threating workers well this will lead to increased motivation , high quality service and great productivity . (b) Is unemployment typically short run or long term ? explain (2mks) It can be both long or short since in short run there can be a shift due to changes in inflation expectation while in long run inflation will increase as aggregate demand shift this is due to expansionary economic policies . (c)Explain how an increase in the price level affects the real value of money (2mks) It will increase the demand for money in that money will be required to be broken into smaller portion so as to buy smaller quantities of goods and services . (d). what are the cost of inflation?(2mks) (i)Reduce international competitiveness When there is high rate on the exported goods there will less competition therefore leading to fall in export . Uncertainity high uncertainity lead to people not to know what to spend money on. (ii) If inflation is less than expected who benefits debtor or creditor ? The debtor will benefit because he will have use the...
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...TCP/IP MODEL TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet. It can also be used as a communications protocol in a private network (either an intranet or an extranet). When you are set up with direct access to the Internet, your computer is provided with a copy of the TCP/IP program just as every other computer that you may send messages to or get information from also has a copy of TCP/IP. TCP/IP is a two-layer program. The higher layer, Transmission Control Protocol, manages the assembling of a message or file into smaller packets that are transmitted over the Internet and received by a TCP layer that reassembles the packets into the original message. The lower layer, Internet Protocol, handles the address part of each packet so that it gets to the right destination. Each gateway computer on the network checks this address to see where to forward the message. Even though some packets from the same message are routed differently than others, they'll be reassembled at the destination. TCP/IP uses the client/server model of communication in which a computer user (a client) requests and is provided a service (such as sending a Web page) by another computer (a server) in the network. TCP/IP communication is primarily point-to-point, meaning each communication is from one point (or host computer) in the network to another point or host computer. TCP/IP and the higher-level applications that use it...
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...Jenell Davis 12.21.12 IS-3220 Assignment 1 TCP/IP stands for Transmission Control Protocol/ Internet Protocol. TCP is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received. IP responsible for moving packet of data from node to node and it forwards each packet based on a four byte destination address also known as the IP number. The Internet authorities assign ranges of numbers to different organizations. The organizations assign groups of their numbers to departments. IP operates on gateway machines that move data from department to organization to region and then around the world. DNS stands for Domain Name Space and it has three major components, the database, the server, and the client. The database is a distributed database and is comprised of the Domain Name Space, which is essentially the DNS tree, and the Resource Records that define the domain names within the Domain Name Space. The server is commonly referred to as a name server. Name servers are typically responsible for managing some portion of the Domain Name Space and for assisting clients in finding information within the DNS tree. Name servers are authoritative for the domains in which they are responsible. They can also serve as a delegation point to identify other name servers that have authority over subdomains...
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...TCP/IP OSI MODEL TCP/IPMODEL OS MODEL Eric Jones 1/31/2014 TCP/IP MODEL OS MODEL TCP/IP is a set of protocols that allows communication between to different computers. It separates networking functions into different layers. Each layer has a different task that is similar to another layer or functions. The TCP/IP is a short version of the OS Model it has four layers instead of seven. TCP/IP is the language of how computers communicate with other computers through the internet. TCP/IP is not a single network protocols it’s a suite of protocols. The TCP layer handles the message being sent and breaks it down into small units called packets which are transferred over to the network. The IP layer is most concerned about transmission. By using unique IP addresses assign to every active receiver on the network. TCP/IP combines the OSI application and the presentation layers and supports flexibility in hostnames and also handles Dns errors and mapping domain names. The OSI also known as the reference model it provides a method of standards and protocols which can be compared to assist in other connectivity. Most developers today now use a reference model/OSI Model learn how transmissions are framed and created to translate to other systems. I it begins with the physical layer of the transmitting system and travels through the other layers to the application layer. Once the data reaches the application layer it is processed by the receiving system. In some cases, the...
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...The internet protocol suite is the protocol stack used on the internet. It is usually called TCP/IP after two of its most important protocols but there are other protocols as well. The TCP/IP is based on a five-layer model for networking. These layers are the physical, data link, network, transport, and application layers. The physical layer contains all the functions needed to carry the bit stream over a physical medium to another system. This layer has four parts: mechanical, electrical/optical, functional, and procedural. The mechanical part specifies the physical size and shape of the connector itself so that components will plug into each other easily. The electrical/optical part determines what value of voltage or line condition determines whether a pin is active or what represents a 0 or 1 bit. The functional specifies the function of each pin or lead on the connector. The procedural details the sequence of actions that must take place to send or receive bits on the interface. The Ethernet twisted- pair interfaces from IEEE are common implements of the physical layer that includes these four part With only the physical layer, a system would have no way to tell another system to get bits ready. The data link layer solves this problem by organizing the bit stream into a data unit called a frame. The data link layer moves bits across the link and can add reliability to the raw communications link. The data link layer can be very simple, or make the link appear error free...
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...Open standards are formats that have been accepted by the industry through formal process that are readily available by the industry. Some of these open standards include such prefixes as: HTTP, HTML and TCP/IP. The benefits of open standards are you have the option not to be locked into one vendor. Since the specifics are open and detailed another vendor could come in and also give work and or solutions to the project. Another benefit would be it is easier for systems using different vendors to be able to adapt to the technology and communicate with each other. Therefore open standards are here to stay and further the internet and other projects well from what it is now. Layered architecture is beneficial to society for the reason of easily organizing the tasks at hand. With this method it not only pertains to networking but to real life as well. Layered architecture is not a new process it has been around for quite some time. A protocol is a set of rules that allows the communications between computers on the network. These rules help regulate the guidelines of speed data transfer and access method. A society based protocol would be like a motorcycle club. For example the network would be the president and the computers would be the other members. The protocol would be the Sgt of Arms as for he would be the one that controls the communication between he members and the president. The four types of different networks are LAN (local area network), WLAN (wireless...
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...NT1210T In the past, networking was often associated with interacting with other individuals to develop contacts, usually to build rapport and further their career. The groundwork put forth during that period was time consuming and tiresome. Telephone, written mail, or conducting a face-to-face meeting prevailed as their main method of communication. Fast forward to today, the click of a mouse button sends out e-mails to a handful of individuals or connects video conferencing calls between people across the globe. The term networking evolved and took on new meaning through the advancement in technology. The world has changed with the way technologies in computers and communications have developed over the years. Interconnecting individuals throughout the country, let alone the world, is a proven necessity in today’s world. The invention of the internet has come to be known as one of the most prevalent methods of communication in modern day. The internet itself is simply a large network of computers connected together via some type of connection communicating back and forth. While many individuals are exposed to the internet on a daily basis, those individuals may not know the complex process that the information goes though. Enormous amounts of ones and zeroes are processed and translated daily throughout the internet. The basis of how we communicate with a computer includes inputs turned into these bits, processing these bits, and producing an output. Fortunately, when...
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...Axia College Material Appendix C OSI Model Key Terms Table Use the table to define the key terms related to the OSI Model. Describe the functions of any hardware connectivity devices and tools listed. | | |Function | |Term |Definition |(if applicable) | |Physical layer |Is responsible for the actual transmission |Media, signal and binary transmission | | |of the bits sent across a physical medium | | |Data link layer |Is responsible for providing error-free |Physical addressing | | |data transmission and establishes local | | | |connections between two computers or host | | |Network layer |Is concerned with the addressing and |Path determination and logical addressing | | |routing processes necessary to move data | | | |from one network to another ...
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