Network Design Project It/230 Final Paper

Network Design Project Art Meyer IT/230 Pernell Curtis 11/27/2011 Executive Summary The Tri-Corp company is need of a complete networking solution. Tri-Corp has two offices, one in Phoenix, and the other in Tucson. The main office in Phoenix is a large 4-story building with 50 workstations and 10 network printers. The Tucson office has five separate workstations and three network capable printers. The clients use Outlook exchange web server for their email communications; both offices require data transfer on a daily basis. Each user requires access to the internet and the shared data stored on the nine clients workstations.DSL, cable, and T3 network solutions are available to the clients. The Tucson clients have a cable internet connection with 8mbps max upload and download limit. The physical layout of the Tucson office is a single story design where the workstations are located in five separate offices in a large building; an unused storage closet is located in a central point in between the offices of that building. Tri-Corps needs a reliable network, with a VPN service to accommodate the needs of traveling executives, upper management, and a growing workforce.Company executives at Tri-Corp have requested a remote access solution as part of their systems upgrade. The company desires its employees to have access to the network from their home PC’s and laptops as a method to help improve productivity and eliminate unnecessary travel and paperwork. In order to function more efficiently, many companies across the globe require remote access to their server systems. A remote access solution will provide Tri-Corp with a proven method to retrieve data from remote locations and them with the opportunity for their executives to complete necessary tasks on the go.However, remote access may provide intruders a method to access Tri-Corps secure data. These vulnerabilities may expose the risk of exploitation and have caused irreparable damage to other companies i n the past. Successfully implementing Tri-Corps remote access solution requires careful planning to protect their data and avoid unwanted attacks by unauthorized users. In addition to the Enterprise system upgrades, Tri-Corp needs to design and implement a disaster recovery plan and review system security policies.While some disasters are unavoidable and vary in type and magnitude, system security attacks are avoidable when companies enforce their information policies and protect their resources. Tri-Corps offices may contain vulnerabilities because they offer remote access to company data to many employees in both locations. Cabling Specifications The shield twisted pair (STP) or unshielded twisted pair (UTP) cable are what connects computers to the switch on the Star Topology network10Base-T is one of the Ethernet standards for cabling in a network environment. 10BaseT uses a twisted pair cable with a maximum length of 100 meters.Standard 10BaseT operates at 10 Mbps. It is commonl y used in a star topology. Gigabit Ethernet (CAT6) over twisted pair copper wires is the preferred cabling specification for high speed data transmissions. Transmission rates in this cabling specification may reach speeds of up to 1000 Mbps. CAT5 T/100 base cables will provide adequate data transfer for most other applications. Local Area Network (LAN) Topologies In the star topology, instead of having a direct connection to each other, the systems are connected to a central device, such as a network switch or a router.One definite advantage the star topology provides is network stability. For example, in the star topology, when one system goes down, it does not bring the rest of the network down with it as it does in the bus or ring topologies. The star topology is the most prevalent topology in use today. The physical topology of the star network contains six different classifications; namely point-to-point network, ring network, mesh network, bus network, tree network and star ne twork. Of these six, the star network is one of the most commonly utilized network topologies.According to definition, the term ‘star topology‘, refers to a network wherein all the nodes are connected individually to one common hub (Naik, 2011). Simply stated, the stat topology is a network topology wherein transmission stations connect to the central node in a configuration where the design of the network stations resembles the shape of a star. Essentially, the star topology design may be likened to the spokes on a wheel, all connected to the central hub. In this network configuration, the exchange of date is only possible through an indirect connection to the central node; this connects all other nodes to the network.As with various other types of network topologies, the star topology has its own set of particular advantages and disadvantages. These factors require careful consideration in regards to the feasibility of the network setup. When evaluating this topology, careful comparison to other network solutions and consideration of all available options helped to discover which solution would provide Tri-Corp with the best answer to meet their needs. It is very easy to install and manage star network topology because its functionality is the simplest among the topologies.Because all computers rely on the central hub, troubleshooting a star topology network is much easier, therefore, any problem, which leaves the network inoperable, leaves a direct path to the central hub. This feature simplifies troubleshooting by offering a particular spot for error connection and at the same time, the reliance is very high on that single point. In star topology, the data packets do not have to make their way through various nodes; this ensures that the data transfer is fast.Consequently, the fact that the data packets only make it through three different points also guarantees that the data is safe. Because the nodes do not connect to each other, problems in one node do not affect the routine of other nodes in the network. Since all the computers on the network have independent control of their networks and are only dependant on the central hub computer, failures in transmitting data and other possible problems in this area are less likely to occur. In addition, if the hub is safe then every computer in the network is safe.This type of network provides more privacy than any other network. Additions, such as new machines or replacing older units are much easier in the star network topology, since the network will not experience any disruption to facilitate changes. The primary problem with star network topology is the fact that it is highly dependent on the central hub functioning properly. Additionally, network size is dependent on the number of connections available on the hub. This network type requires more cable when compared to other topologies, such as linear bus topology.Therefore, the cost and expense of a star topology runs hig her and the expenses incurred are relatively high. Since the performance of the total network depends on the performance of the hub, a slow server will cause the entire network to slow down. As mentioned earlier, the star network topology requires more cable to connect the network together than the usual Bus topology. For this particular network setup, the recommendation is to use is the RJ45 or the Ethernet cables. To be specific, this network setup requires a gigabit 48-port switch and CAT6 base T/1000 Ethernet cabling to both the IT and the graphic design department.The other departments will use CAT5 base T/100 cabling. In a Star Network the entire network is dependent on the hub so if the entire network is not working then there could be a problem with the hub. Since all the computers on the network have independent control of their networks and only dependant on the central hub computer, the failures in transmission and other possible problems in this area are less likely. In addition, if the hub is safe then every computer in the network is safe. This type of network also offers more privacy than any other network.A Star Network Topology is best suited for smaller networks like Tri-Corps and works best when there is limited number of nodes. The primary objective is to ensure that Tri-Corps hub or the central node is always functioning and that all extra security features are added to the hub because it s the heart of the network and the stability of the network relies directly on the stability of the central hub. Wide Area Network (WAN) Design Tri-Corps two offices, one in Phoenix and the other in Tucson require a WAN network to effectively communicate and share data and resources.The main office in Phoenix is a large 4-story building with 50 workstations and 10 network printers. The Tucson office has five separate workstations and three network capable printers. The clients use Outlook exchange web server for their email communications and require mini mal amounts of data transfers between the offices. Each user requires access to the internet and the shared data stored on the nine clients workstations. Both DSL and cable internet service are available to the clients. The Tucson clients have a cable internet connection with 8mbps max upload and download limit.The physical layout of the Tucson office is a single story design where the workstations are located in five separate offices in a large building; an unused storage closet is located in a central point in between the offices of that building. The current system in the Tucson office uses a non-commercial five-port router; each computer connects to the router through a Cat5 Ethernet connection. The first step is to discover the bandwidth needs and average user loads. Data from Cisco (Boda, 2009) suggests the average broadband connection generates approximately 11. gigabytes of Internet traffic per month. We will use this figure to calculate the bandwidth needs of this company. Calculating with 10 users and a five-day, forty-hour workweek as our model for the Tucson office, we can calculate average daily consumption to be approximately 5. 7 gigabytes per day of bandwidth consumption. The current cable internet allows for 28 gigabytes during an eight-hour period (multiply 8mbps x 3600, the number of seconds in an eight, hour period, and divide by 1024) should provide a stable connection throughout the day as all ten users are rarely on the network at once.The setup of the Phoenix offices is more complex; they require a T3 connection to accommodate the IT and the Graphic Design departments. The third floor houses the IT department, the first floor houses the reception staff, along with lower level management, the second floor houses the graphic design department, and the fourth floor houses the operations staff while the fifth floor houses upper management. The current system in the Phoenix offices uses a network hub and repeaters. Both the IT and graphic de sign department complain they do not have sufficient bandwidth to meet their needs.Upper management complains that the system on their floor is too slow. The Tucson offices complain they experience difficulty sending and receiving data and email from the Phoenix offices, and connections time out frequently. The current system in the Tucson offices lacks design and will not allow for additional users or adding network printers. Additionally, aside from the firewall provided by the router, no real network security is in place and the workstations cannot communicate with each other in either location. The Phoenix offices need increased speed and greater bandwidth. Both offices require better communications etween the workstations to increase efficiency. The recommendation for the Tucson offices is to install a server system using Windows server 2003, and a VPN; this office will utilize the star topology, thus allowing for growth and easier diagnostics. In addition, failure of one works tation will not affect the entire network and the speed will be optimal. The server software provides several benefits. Multiple applications are available to run in the Server 2003 environment, including financial apps, database programs, and e-mail exchange operations as well as web server and Internet programs.Domain operations are included in the software, something that will become an important resource by adding security and the ability to the local and group policies of the network. Additionally, if Server 2003 is not utilized as a domain controller, then it can run simple network operations using peer-to-peer structures (Garza, 2010). An extensive amount of shielded twisted pair Cat5 cables will be necessary to connect each workstation and the network capable printers. The VPN system will allow the users to connect remotely to their workstations and the company intranet. The Tucson office will utilize the central closet as a server room.The server will handle all application s and house the data storage. The server will have a connection to a primary switch; this switch will also handle the data transfer between the local PCs of each office. The switch accomplishes two tasks; since connections from one port to another are made on an as needed basis (Axia College, 2005), this will eliminate traffic collisions and create faster point to point connections. The switch will be connected to ports on the private network switch allowing for access to the application and data servers, along with the DNS and Active Directory server.Since the data transfer needs are minimal, the switch does not need Cat6 cabling; Cat5 STP will work, gigabit switches will not be necessary. Security from outside traffic will be enforced by closing the ports to outside traffic. Users will access the internet via an Internet Security and Acceleration (ISA) server, which will be connected to the public network. The recommendation for the Phoenix office will also include a new server an d the Windows server 2003 platform. Both offices will use the same VPN, however, in the Phoenix offices, only upper management will have access to the VPN from outside the building.The existing network hub will be replaced by T/1000 switches connected to gigabit LAN network interface cards on each of the workstations in the graphic design department as well as those in the IT and upper management. Gigabit LAN adaptors are required on the servers to accommodate the high bandwidth needs of these departments. The reception area, lower management, and Operations will connect to standard switches using a T/100 base, thus eliminating the problem of network congestion in the departments where more bandwidth is required, and limiting the bandwidth where it is not necessary.Cat6 cabling will be utilized on the second, third, and fifth floors to accommodate the bandwidth needs of the high end users. CAT5 cabling will be used throughout the rest of the system and should easily meet the needs o f the end users in the other departments. The primary cost of upgrading both systems will be in the cabling; both offices will require an extensive amount of CAT5 and CAT6 networking cables.The server systems and switches will incur the second highest cost; both upgrades are necessary to provide the company with greater ease of use and transitional growth opportunities Updating the current systems and switching to Windows server 2003 will provide both offices with greater stability, efficiency, and increased security. Updating the Phoenix offices from hubs to switches will increase the flow of network traffic and allow for greater communications between both offices and all workstations.The Tucson offices will benefit from less frequent connection time outs and rapid data transfer to and from the Phoenix offices. Additionally, both offices will be more prepared for rapid growth. The Tucson offices will show increased productivity by networking all of the printers. The Phoenix office s will benefit from as the IT department and graphic design will have the necessary bandwidth to meet their needs, while upper management will spend less time waiting on reports and data necessary to make day to day decisions that will affect the company’s long-term growth strategies.Upgrading the current systems is not only a wise decision, it is the only logical decision for a company that is primed to move ahead and take control of the market in its area and expand into more profitable markets in other cities as well. Network Protocols VPN users gain remote access to their LAN through the internet. VPN’s are network links formed by connecting to an ISP and the company LAN. These connections use technologies such as sophisticated packet encryption to secure the data link. This is especially important, as the information is travels across a public network.The advantage of using a public network versus dedicated connections is the cost; many companies take advantage of VPN technology to provide remote access without compromising security. Dial-up networking is the simplest way to connect to the Internet. Computers connect over the phone line using a modem. Users must pay for a subscription to an ISP like AOL. Dial-up connections are much slower than broadband and the speed maxes out at 33. 6 Kbps. Some applications will work with satisfactory results; more and more applications require greater connection speeds even when performing simple tasks such as transferring files.Both applications require user name and password login information; that however, is where the similarities end. VPN users benefit from a secure, encrypted connection that is firewalled from intruders and typically monitored by a network administrator to ensure the privacy of the connection is not compromised. Dial up users connect to a public network and may be susceptible to outside attacks. Network Remote Access Company executives at Tri-Corp have requested a remote access sol ution as part of their systems upgrade.The company desires its employees to have access to the network from their home PC’s and laptops as a method to help improve productivity and eliminate unnecessary travel and paperwork. The company requests that all upper management be granted unlimited access to all files and network resources and permissions. Additionally, they wish to grant access to all mid-level managers, the operations manager, and the entire graphic design department. Support staff and non-salaried associates desire access to the company site for employee benefits and access to daily reports.Tri-Corps enterprise system runs two servers, one in the main branch located in Phoenix; the other in the support branch located in Tucson. Both branches utilize Microsoft Server 2003 software, and a star topology. Outlook is among the programs that are most widely used by the executive branch, Publisher and Adobe Illustrator top the list among the graphic design department. O perations use a simple data storage program that breaks down cost and projects business forecasts. Tri-Corp believes their company will function more efficiently by granting its employees remote access to their server systems.Whereas it is true remote access does provide many companies with a proven method to retrieve data from remote locations and offers their users a chance to complete necessary tasks on the go, Tri-Corp will be at risk; remote access also offers intruders a way in to Tri-Corps secure data. If these vulnerabilities expose the company to exploitation, the damage may prove to be irreparable. Companies who plan to use a remote access solution need careful planning to protect their data and avoid unwanted attacks by unauthorized users.Therefore, the question lays, â€Å"Should Tri-Corp use Dial-Up or VPN to complete their remote access solution? The first step is user control; it is imperative to control which users can access the network from outside the company. Ne twork access should be granted only for users who need it; the likelihood is that not everyone is likely to need network access from outside the company. Whether Tri-Corp decides to use Dial-Up or VPN they must set up remote access accounts for remote users that are separate from their normal accounts, and make these accounts more restrictive than their normal LAN accounts (Axia, 2006).The company executives may believe this security measure to be impractical; however, this strategy is vital, particularly for users who normally have broad security clearance (Axia, 2006). The advantage of using Dial-Up is the Dial-back feature. Dial-back is a feature whereby you securely enter the phone number of the system from which users are calling (Axia, 2006). Users requesting remote access from a fixed location such as a private residence are ideally suited for a Dial-Up remote access connection with the dial-back feature.Once these users connect, they dial the system, request access, and then the remote access system terminates the connection and dials the preprogrammed phone number to make the real connection (Axia, 2006). The home based computer then answers the call and proceeds to a normal connection. This service offers greater security for home based users because any other user who may attempt to gain access will not be allowed access with this feature enabled. One more key advantage of a dial-up remote access server (RAS); RAS solutions require employees to onnect to the corporate network via a direct telephone call to modem banks installed at the network edge (â€Å"Remote Access Vpn Solutions†,  2000). Three key differences separate dial-up and VPN architectures; the first being that direct dial-up does not utilize the internet to avoid incurring long distance phone charges. Next, the corporation setting up the dial-up connection is responsible for providing modem banks (modem banks are similar to network hubs or switches). Finally, encryption technol ogies are not required because the network traffic passes through non-shared links.Undoubtedly, granting remote access may increase productivity and effectiveness by giving employees direct access to information from anywhere in the world. One primary example is email access; this factor alone makes a big difference for employees that are constantly on the go and rely on email to communicate from remote locations. The business benefits of using a VPN delivers several advantages versus RAS solutions. VPNs offer two distinct cost advantages; first, Internet connections, which are typically local calls, are much less expensive than toll free or long distance dial-up connections.This consideration typically is what convinces most organizations to apply a VPN rather than an RAS solution. Secondly, the equipment cost of purchasing and maintaining a VPN is much more cost effective than standard RAS equipment. Installation and use of VPN’s may yield a cost savings of up to 70 percent over a standard RAS system. Comparatively, most companies discover that remote access VPNs pay for themselves in cost savings in a relatively short period. By way o f contrast, RAS systems only incur greater cost throughout the course of time, especially if upgrades or adding more users is necessary.The amount of access available is dependent on the scaling system and how the VPN distributes the client’s software. Scaling a remote access may also necessitate increased bandwidth of the company’s Internet connection. As soon as the VPN gateway is operational, the company may change the scaling system to support anywhere from a few hundred to tens of thousands of users. The option of scaling for RAS solutions is not as trouble-free and requires the use of additional hardware and adding phone lines.The widespread use of broadband Internet service now offers VPN clients an inexpensive solution to connect corporate networks by utilizing the World Wide Web to connect from ou tside the company walls without losing speed and compromising security. This is a very attractive option for mobile users in particular. Dial-up solutions do not always provide the same security and ease of use as this option. In some cases dial-up solutions may very well remain the best solution; many company’s still employ this solution as part of their remote access services for their fixed locations.With proper maintenance, this solution will still serve the needs of a smaller client base. However, if the client base grows rapidly and significantly, they may soon overload the RAS system and discover they need to move on to a different solution. The recommendation for Tri-Corp is to utilize a VPN solution. However, the executive branch will utilize the dial-up service from their fixed locations, such as their place of residence. This will offer greater security by using the dial-back feature to ensure the user is not an unauthorized intruder.This will also remain cost effe ctive as the executive staff numbers only eight individuals. Graphic design, operations, and the rest of the support staff will gain access through the VPN software in Microsoft’s Server 2003 package. However, each department will only have access to the resources that are consistent with their job requirements. Operations will have access to the database and Outlook; the graphic design department will have access to their saved projects files and Outlook. The support staff will only have access to the company human resources sites and limited access to non-confidential company information.The key elements of a successful remote access implementation will include security, performance, high availability, and client management. A meeting with the Tri-Corp company will outline and clearly define their specific requirements in each key area to discover the solution that will serve the company’s needs. Utilizing both dial-up and VPN solutions will offer this company the be st of both worlds; security and performance as well as greater productivity and performance without the need for incurring greater cost. Network Business ApplicationsThe recommended applications for Tri-Corp will include Microsoft’s Office Professional suite and the Microsoft Server 2003 software for the local servers. Outlook will replace the exchange server provided by Microsoft. This will provide Tri-Corp with more flexibility and aid in the ease of adding new email user accounts. POP3 and SMPT will require proper configuration to enable this service. In addition to the Enterprise system upgrades, Tri-Corp needs to design and implement a disaster recovery plan and review system security policies.While some disasters are unavoidable and vary in type and magnitude, system security attacks are avoidable when companies enforce their information policies and protect their resources. Tri-Corps offices may contain vulnerabilities because they offer remote access to company data t o many employees in both locations. Network Security We will first address the issue of Enterprise Security and best practices. Microsoft has developed a four-part checklist, which focuses on the following key points: Assessing the environment, protecting the network, protecting servers and clients, and finally, monitoring the environment (Microsoft 2011).Using this guide will help increase Tri-Corps security and reduce the risk of outside attacks. Assessing the environment requires learning all of the components within the infrastructure. Tri-Corp needs to identify all assets and security issues while continually monitoring the quality of the security program (Microsoft 2011). Their first step will be to partner upper management with the IT staff so they may both focus on establishing an ongoing process to classify and examine all security risks. Failure to establish this vital communication will absolutely place the company at risk with the largest security problems.Next, protecti ng the network; Tri-Corps server system will utilize both Secure Socket Layer (SSL) encryption, and a Public Key Infrastructure (PKI) to aid in maintaining network security. Secure Sockets Layer (SSL) encryption is one of the leading technologies used today to secure web sites, intranets, extranets, and other server-based applications (IT Observer, 2009). Using SSL along with special server digital certificates will provide the security handshake and the data encryption to prevent eavesdropping and secure the integrity of data transmissions (IT Observer, 2009).Although SSL and PKI will help provide network security, additional security measures are necessary to protect the servers and clients. Tri-Corps server will utilize a software firewall such as Zone-Alarm, and must maintain up to date anti-virus and Trojan protection software such as Kasperksy, Norton, or McAfee. Next, the IT department must ensure every security patch for all operating systems and applications are applied as soon as they become available. The final focus point in network security, monitoring the environment, entails the weakest link in all network security, people.Monitoring the environment is more than watching and reacting; Tri-Corp must establish a proactive strategy to audit the network and discover poor practices and configurations. Password rules are a primary example; passwords must contain both upper and lowercase characters and one symbol. Only secure messaging through company provided and monitored email accounts will be allowed, no instant messaging or chat rooms; all emails must pass a virus scan before the recipient will be granted access to view the message.With a detailed information policy in place, proper training, consistent, proactive monitoring, Tri-Corp will protect its data and avoid the mess and disruption of security leaks. Once this policy is in place, Tri-Corp will need to move on to its disaster recovery plan. Tri-Corps needs to have a disaster recovery plan i n place, to return to normal after disaster has struck. Defining disaster means an abrupt disruption of all or part of its business operations, which may directly result in revenue loss (Cisco, 2008).To reduce disaster losses, it is imperative to have a first-rate disaster recovery plan for every business subsystem and operation within Tri-Corps walls. Backup and Disaster Recovery Every time a business encounters a disaster, the company always points to one or more causes and effects. The causes may be anticipated, or a result of human, or mechanical origin, and can range from events as miniscule as a minor hardware or software components malfunctioning to commonly recognized events such as earthquakes, fire, and flood (Cisco, 2009).These disasters may cause small interruptions or may lead to total business shutdown for days or months. Occasionally, these disasters have proven to be fatal to unprepared businesses. Forming a disaster recovery plan begins by recognizing the root cause and effect, followed by a detailed analysis of probability and severity, and ranking them in terms of their business priority. The outcome is an official evaluation of threat and a disaster recovery plan that takes into account all available recovery means.In simpler terms, Tri-Corps IT staff needs to determine what types of disasters are most likely to occur and rank them in order of probability. Afterwards, Tri-Corp must create an action plan that encompasses detailed steps to return business to a state of normalcy in the event of the given disaster. Finally, Tri-Corp must form a Disaster Recovery Committee to assume responsibility for rehearsing, carrying out, and improving the disaster recovery plan on a continual basis. Tri-Corps disaster recovery plan must include a data backup plan in the event the company’s database is compromised. The recommendation is to use IBM’s Tivoli software.IBM’s backup and recovery service provides companies with a backup and d isaster recovery solution that includes cloud backup, remote office, unified recovery, and virtual server protection. Their Tivoli Storage Manager received the 2011 CRN Channel Champions Award because of the quality, reliability, support, and scalability of their solution. Many other companies offer backup and disaster recovery solutions, however, based on my research IBM offers the most complete and reliable solution. IBM’s backup and recovery service provides companies with a proven solution for managing their storage needs with a central backup solution.This service uses smart data movement and smart data store technology; together, these technologies complete backups and restores quickly and efficiently while still providing the client with the flexibility to change and adapt. Additionally, the IBM Tivoli suite of storage products supports more than a dozen OS platforms, along with several network connectors, and more than 500 storage devices. (Art W Meyer,  2011,  pa ra. 2,4) Using these two key components will ensure Tri-Corp will complete the necessary preparation to survive disaster and avoid external attacks.Additionally, this plan will ensure that the resources required to keep the business going are available to key personnel. The questions regarding what to do, how to do it, and the ever- present need for communication to critical data is a key component in maintaining Tri-Corps success. However, no amount of planning provides the desired effect without a thorough understanding of the organization and its inner workings. Tri-Corp must incorporate its processes, people, and systems with precise, exacting detail to aid in a seamless transition.Following the preceding recommendations will help assure Tri-Corp does not fail because of ignorance. This recommendation will protect Tri-Corps valuable data assets and help the company to keep moving forward.References . Axia College. (2005). 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