2 Assessment Criteria Learning Outcome The learner will: Pass The assessment criteria are the pass requirements for this unitThe Learner can:MeritTo achieve a merit the evidence must show that, in addition to the pass criteria, the learner is able to:DistinctionTo achieve a distinctionthe evidence must showthat, in addition to the passand merit criteria, thelearner is able to:1 Understand web architecture and componentsP1 Outline the web architecture and components which enable internet and web functionality2 Understand the factors that influence website performanceP2 Explain the user side and server side factors that influence the performance of a websiteP3 Explain the security risks and protection mechanisms involved in website performanceM1 Compare and contrast current interactive websites for performance and securityD1 Discuss the impact that cases of website security breaches have had on society3 Be able to design websitesP4 Using appropriate design tools, design an interactive website to meet a client needM2 Produce annotated design documentation for an interactive website to meet a client need4 Be able to create websitesP5 Create an interactive website to meet a client needM3 Implement CSS in an interactive website to improve the site to meet a client’s needsD2 Carry out acceptance testing with client on an interactive website
3 Understand web architecture and components Learners should gain an understanding of what each of the architecture, components and protocols are as identified in the teaching content. This can be facilitated by group discussion, exercises, presentations, or group research tasks.Assessment criterion P1 could be evidenced by the use of a report or presentation, delivered to a group and evidenced through the presentation, and supported by a tutor observation sheet, or recorded evidence. Each of the listed topics in the web architecture, components and protocols section of the teaching content should be covered, by an explanation of what it is and what it does.
4 LO1 Understand web architecture and components - Architecture Internet service providers (e.g. Virgin Media, BT, Sky)Internet service providers are there for a reason, companies and individuals need to either connect through a provider or use their own T-Line like a T1. ISP’s provide a service that most individuals are not aware of, from minor hosting to providing a static IP address. The range of ISP’s is broad, each sells a connection package with phone options and each can be measured in terms of speed of connection, bandwidth and for most, a small degree of site or file hosting.Speed of connection – this is how fast an individual file can go from the website to your screen, measures in Megabit speed which is 1/8 of a Megabyte per second. The faster the speed the faster a page opens.Bandwidth – this is how large a file can be downloaded at one time and can be compared to road width, smaller the bandwidth, the more buffering a file has to do to load.Static IP – Used by business to limit down activity such as blocking, easier to block and restrict a static address than a dynamic address, whereas dynamic addresses are more difficult to hack or be subject to DDOS attacks.Hosting – a lot of small companies host on their ISP and bounce to a registered domain name from. This is good for small businesses as the storage space for small sites is already there. Bouncing the web address is not seen by the customers and it is a secondary site that makes it more difficult to hack.P1.1 – Task 1 – Describe, with evidence, the purpose and function of ISP’s for a specific client.
5 LO1 Understand web architecture and components - Architecture Web hosting services (e.g. free hosts; Google Sites, Free-space; paid hosts; JimdoPro, Fasthosts)Web hosting differs from ISP’s because they provide a place to store, locate, display and manage website functions. Where ISP’s can bounce, hosts store. The difference is the range of hosts is the service they provide for that fee. These services include:Database management through SQLAuto redirecting of IP addressingexchangingVirtual Private networkingDedicated server activityThe difference between pricing strategies depends on the level of service the user requires, free hosts like Google share the space but not the activity, Bit and tinyurl provide space and a small degree of activity management whereas fasthosts and others provide more management facilities such as forums, secure logins and database management, shopping basket protection, blog and wiki activity etc. None of these provide filtering, that is something that the user still has to manage like forum maintenance and management. Ultimately the provision of hosting is the difference between a look-at-me site and an managed shopping experience.P1.1 – Task 2 - Describe, with evidence, the purpose and functions of Web Hosting for a specific client.
6 LO1 Understand web architecture and components – Architecture - Domains Part 1 - Transfer Protocol– Hypertext Transfer Protocolhttps:// – Hypertext Transfer Protocol, Secureftp:// - File Transfer Protocol for FTP site. Allows upload/download of files.Part 2 – www (which part of internet is being addressed)Part 3 – domain name – name of organisation that controls the site that the page is stored onPart 4 – indicates the type of organisation (.co/.sch/.gov/.edu/.org etc)Part 5 – the country in which the site is locatedPart 6 – sub domain or webpage currently viewingPart 1Part 2Part 3Part 4Part 6Part 5
7 LO1 Understand web architecture and components – Architecture - Domains Web addresses as seen in the previous slide are broken down for a reason. First there was IP addresses, then the web grew to the point when remembering all those numbers was impossible. When the system of DNS came into place, the translation of IP addresses to wording allowed businesses, government offices, companies and individuals to generate their own unique address that was more memorable for the customer.How difficult would Easyjet.com find business if the customer has to remember 12 numbers, or Thetrainline, Google, Amazon, all branded names based on their DNS name rather than their IP.Internet Service Provider (ISP)has unique IP (Internet Protocol) addressfour numbers separated by full stopsDomain Name System (DNS)translates IP address numbers into domain nameWithout the DNS you would have to remember numbers instead of names.For example – typing would lead to the same page asURL (Uniform Resource Locator)standard address used to find a pageP1.1 – Task 3 - Describe, with evidence, what DNS and URL are and what it does in terms of securing business, naming and address management.
9 LO1 Understand web architecture and components – Web Servers The term web server can refer to either the hardware (the computer) or the software (the computer application) that helps to deliver web content that can be accessed through the Internet. The most common use of web servers is to host websites, but there are other uses such as gaming and data storage The primary function of a web server is to cater web page to the request of clients using HTTP. This means delivery of HTML documents and any additional content that may be included by a document, such as images, style sheets and scripts.A user agent, such as a web browser or web crawler, initiates communication by making a request for a specific piece of information using HTTP and the server responds with the content of that resource or an error message if it is unable to do so.For companies that prefer to manage their own hosting they will need specific hardware to store, serve, process and manage user accounts and internet activity. This is called a Web Server, sets an open traffic line between server and outside hosting and allows the user to manage their own business.Managing the website internally allows the users to change anything without the need to upload, making the changes automatic and live each time. Longer term this is more beneficially for a company for the sheer reason of being able to manage your own content and expand through software rather than proxy.
10 LO1 Understand web architecture and components – Web Servers The two main types of server for this is IIS and Apache. Internet Information Services (IIS) is a server designed to work with a Microsoft environment, and manages web activity in terms of modules, Security, Content, Compression, Caching, Logging and Diagnostics which all add up to a website management bundle for all activity on the site. Ruby on Rails, ASP (.net and classic) and Python are all languages that work out of the box on IIS whereas they have it be added to Apache as modules to be managed. More importantly it comes free with Microsoft Windows and functions well within with similar coding parameters.Apache server is often referred to as simply Apache, a public-domain open source Web server developed by a loosely-knit group of programmers. Core development of the Apache Web server is performed by a group of about 20 programmers, called the Apache Group. However, because the source code is freely available, anyone can adapt the server for specific needs, and there is a large public library of Apache add-ons. It is the most accepted web server because it offers all the functionality of the IIS and is more adaptable. Being free is it’s biggest selling point though it does everything IIS can do with add –ins.P1.2 – Task 5 - Describe, what web servers do and how they work and outline the benefits and disadvantages of IIS and Apache.
11 LO1 Understand web architecture and components – Components - Email is a great way to give your employees the means to collaborate and share information with co-workers, vendors, manufacturers, customers, and students.A mail server is a server that handles the network’s needs. It is configured with e- mail server software, such as Microsoft Exchange Server. Exchange Server is designed to work with Microsoft Outlook, the client software that comes with Microsoft Office. Most mail servers actually do much more than just send and receive electronic mail.Hardware wise this usually is a dedicated server that handles the client (software) processes the tens of thousands of s that come in every day and manages these s to the client. With the server software, s are processed before rerouting. A server application like Exchange Server will:Spam and virus filter through the sBlock DOS attacksFilter for swearwordsFlag up erroneous or dangerous sProcess attachments, groups, reminders, and account information.Manage the folder limits.
12 LO1 Understand web architecture and components – Components - Email servers can be internal or external similar to Web Servers but the need for management is more urgent than web filtering and proxy management. s server work on two levels, Pop3 and SMTP, or incoming and outgoing connections. Once an is sent to a registered company and the server receives it through ISP distribution, the server will then process the through a content filter and pass it on to the relevant internal address.All sorts of actions happen between the receiving and arriving, such as address redirection, filtering, content management, box size management, priority management, delivery and distribution management, backup storage and data logging. This is taken care of by the server.Similarly an online server like Icewarp manages some of these tasks, for a fee. The service they provide depends on the user needs and the annual subscription. This is one step away from Cloud Computing which is more interactive but in the 10 years of development the professionalism and customisation of the online providers has put them on a par with offline providers, except for the individualisation.P1.2 – Task 6 - Describe, what servers do and how they work and outline the benefits and disadvantages of internal vs. external server provision.
13 LO1 Understand web architecture and components – Components - Proxy A proxy server (or Application Gateway) is a server that sits between a client computer and a real server. The proxy server intercepts packets that are intended for the real server and processes them. The proxy server can examine the packet and decide to pass it on to the real server, or it can reject the packet. Or the proxy server may be able to respond to the packet itself, without involving the real server at all.For example, Web proxies often store copies of commonly used Web pages in a local cache. When a user requests a Web page from a remote Web server, the proxy server intercepts the request and checks to see whether it already has a copy of the page in its cache. If so, the Web proxy returns the page directly to the user. If not, the proxy passes the request on to the real server.Application gateways are aware of the details of how various types of TCP/IP servers handle sequences of TCP/IP packets, so they can make more intelligent decisions about whether an incoming packet is legitimate or is part of an attack. As a result, application gateways are more secure than simple packet-filtering firewalls, which can deal with only one packet at a time. A good proxy server will:Learn from attacks and add them to a barred listDownload updates from an online security system like JanetFilter the network as an added level of protection.Act as a barrier, together with the firewall and SSL against DOS attacks.P1.2 – Task 7 - Describe, what proxy servers do and how they work and outline the benefits in terms of security to a company.
14 LO1 Understand web architecture and components – Components - Routers A router is like a bridge, but with a key difference. Bridges are Data Link layer devices, that can’t peek into the message itself to see what type of information is being sent. In contrast, a router is a Network layer device, so it can work with the network packets at a higher level. In particular, a router can examine the IP address of the packets that pass through it. And because IP addresses have both a network and a host address, a router can determine what network a message is coming from and going to. Bridges cannot.Unlike a bridge, a router is itself a node on the network, with its own MAC and IP addresses. This means that messages can be directed to a router, which can then examine the contents of the message to determine how it should handle the message.You can configure a network with several routers that can work cooperatively together. For example, some routers are able to monitor the network to determine the most efficient path for sending a message to its ultimate destination. If a part of the network is extremely busy, a router can automatically route messages along a less-busy route, for example, the router knows that the Rockingham Road is gridlocked all the way through to the A6003, so it sends the message for cars to go on A45 instead.Routers aren’t cheap. For big networks, though, they’re worth it. The functional distinctions between bridges and routers get blurrier all the time. As bridges, hubs, and switches become more sophisticated, they’re able to take on some of the chores that used to require a router, thus putting many routers out of work.Some routers are nothing more than computers with several network interface cards and special software to perform the router functions. Routers can also connect networks that are geographically distant from each other via a phone line (using modems) or ISDN. You can also use a router to join your LAN to the Internet.P1.2 – Task 8 - Describe, what a router does and how they work and outline the benefits in terms of network traffic flow to a company.
15 LO1 Understand web architecture and components – Components - Browsers Browsers (e.g. Internet Explorer, Mozilla Firefox, Google Chrome, Opera, Safari)Browsers exist merely to display results and translate the HTML code from the external and internal sites onto a GUI for the user to read and use. The choice of Browser is dependant on the users preferences rather than needs. They all do the same thing, display results. Browsers come with a small range of additional options to benefit the user and claim loyalty, for example:Embedded in IEProxy and Java blocking in OperaCompatibility with OS like SafariEase of Use like ChromeAdding favourites or stash like Opera.Speed of display like FirefoxFrom within all Browsers is the options for connectivity which allows the easier access to networking. Also the access to history, RSS feeds, setting privacy levels, security settings etc. are all available on any web browser.
16 LO1 Understand web architecture and components – Components - Browsers At the end of the day all browsers are free, some come preinstalled with the OS like IE in windows, Safari on IOS, Firefox in Linux and there is nothing to stop a user from installing other browsers for their own particular reasons. For comparison details click here.Heavy web users need an internet browser that is both fast and secure, and though all browsers enable internet access, not all are created equal. Different browsers can render webpages differently, and there can be a large disparity in performance between the top competitors. The three main things to consider when choosing an internet browser are simplicity, speed and security.P1.2 – Task 9 - Describe what a web browser does and how they work and outline the range of different choices are available for a company.
17 LO1 Understand web architecture and components – Components – TCP/IP The TCP/IP family uses four layers while ISO OSI uses seven layers as shown in the figure above. The TCP/IP and ISO OSI systems differ from each other significantly, although they are very similar on the network and transport layers.Except for some exceptions like SLIP or PPP, the TCP/IP family does not deal with the link and physical layers. Therefore, even on the Internet, we use the link and physical protocols of the ISO OSI 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.
18 LO1 Understand web architecture and components – Components – 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, they'll be reassembled at the destination.TCP/IP uses the client/server model of communication in which a user (a client) requests a service (such as sending a Web page) from another user (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 are collectively said to be "stateless" because each client request is considered a new request unrelated to any previous one.
19 LO1 Understand web architecture and components – Components – TCP/IP You need TCP/IP to connect to the Internet. Realize that there is a difference between installing TCP/IP on your network and installing it for dial-up networking use; these are two separate installations and uses for the protocol.You install TCP/IP to use with the dial-up networking feature. This installation enables you to connect to the Internet by means of a modem. The TCP/IP communicates with Web servers on the Internet. If you install TCP/IP on your network, you use it to connect to the other computers on your LAN. One installation has nothing to do with the other. For more information,Using TCP/IP to connect to the Internet provides you with all the Internet features and advantages, including , Web browsers, and file transfer. Also, TCP/IP includes various programs (which are also protocols) that you can use to access information on the Internet. If you have special needs for FTP or Telnet, for example, TCP/IP provides those programs for you to use. If you plan to expand your network to the Internet someday, your knowledge and use of TCP/IP will help you tremendously. Knowing how to configure TCP/IP will make it easier for you to transfer your Web sites and pages to the Web and to configure clients and servers for the Internet. Having TCP/IP in place means less configuring when you move to the Internet.P1.2 - Task 10 – Define TCP/IP and in terms of web components define the benefits of TCP/IP in constructing and Intranet and Internet presence.
20 LO1 Understand web architecture and components – Components - Email There are two types of components used in private and business, Browser based such as Outlook express and Site based such as GMail, Hotmail, Yahoo Mail etc. Both of these types have their own purposes and often users will use several online and an offline mail program to access their accounts. With modern Smartphones, synchronising accounts is standard practice but users will still maintain a separation between accounts, usually for professional and personal reasons.The difference between the two systems is minimal, once activated they provide the same systems of storage and access, mail, calendars, reminders, CC, BCC, folders structures, tracking RSS accounts, out of office reminders, collaborative calendar sharing, meeting invites and reminders.The difference between offline and online is ease of access, online programs save the s as drafts to be re-accessed, offline programs resend when reconnected. It is the ease of use that defines the multiple accounts, online can be accessed remotely, allows multiple accounts but is also less secure.
21 Program and Browser based email Microsoft Outlook and Outlook Express are programs that allow the user to send and receive mail, manage and sort messages, check and remind the user of their feeds, attach files, and more. The User can read their messages while still attached to the Internet, or they can read and answer them offline if you use a telephone line and ADSL to connect to the Internet. If the User uses a permanent connection, such as a cable modem, their computer is always online. With a permanent connection, they can choose toHave Outlook Express check your mail every 10 minutes, or every 30 minutes, and so on.Create folders to organize your messages, and keep an address book that makes addressing your messages quick and easy.P1.2 - Task 11 – Define the purpose and function of Browser based programs and define the advantages and drawbacks against internal mailing systems.
22 Task ListP1.1 – Task 1 – Describe, with evidence, the purpose and function of ISP’s for a specific client.P1.1 – Task 2 - Describe, with evidence, the purpose and functions of Web Hosting for a specific client.P1.1 – Task 3 - Describe, with evidence, what DNS and URL are and what it does in terms of securing business, naming and address management.P1.1 – Task 4 - Describe, with evidence, the different levels of Design Creation software available and the advantages and disadvantages of online vs. offline creation.P1.2 – Task 5 - Describe, what web servers do and how they work and outline the benefits and disadvantages of IIS and Apache.P1.2 – Task 6 - Describe, what servers do and how they work and outline the benefits and disadvantages of internal vs. external server provision.P1.2 – Task 7 - Describe, what proxy servers do and how they work and outline the benefits in terms of security to a company.P1.2 – Task 8 - Describe, what a router does and how they work and outline the benefits in terms of network traffic flow to a company.P1.2 – Task 9 - Describe what a web browser does and how they work and outline the range of different choices are available for a company.P1.2 - Task 10 – Define TCP/IP and in terms of web components define the benefits of TCP/IP in constructing and Intranet and Internet presence.P1.2 - Task 11 – Define the purpose and function of Browser based programs and define the advantages and drawbacks against internal mailing systems.