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Remote and WAN connectivity. Unit objectives Describe POTS and ISDN circuits, as well as cable, xDSL, satellite and wireless access Configure Windows Server 2003/XP with a modem Discuss Remote Access Services (RAS) and create a dial-up connection in Windows Server 2003/XP
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Remote and WAN connectivity Unit objectives • Describe POTS and ISDN circuits, as well as cable, xDSL, satellite and wireless access • Configure Windows Server 2003/XP with a modem • Discuss Remote Access Services (RAS) and create a dial-up connection in Windows Server 2003/XP • Describe WAN connectivity options • See PPts #1 & 1A: WAN technologies
Topic A • Topic A: Introduction to remote connectivity • Topic B: Installing and configuring a modem • Topic C: Remote Access Service (RAS) and remote access clients • Topic D: WAN connectivity
Remote connectivity • Several options to establish remote connectivity • Modem via POTS • ISDN • Cable modem • xDSL • Satellite • Wireless • Lots of other options not in the book, because they are not “objectives” of the Network+ exam • Leased Lines (although T1 lines, etc are covered) • VPN • Terminal Services • etc.
POTS (or PSTN) • Stands for Plain Old Telephone Service • PSTN: Public Switched Telephone Network • The standard telephone service you subscribe to for making voice calls • The connection between the phone co. and the customer is the “local loop” • Modems connect over these lines. Max rate is 56,000 bps. (v.90 standard). • Many other limitations. • The entire system is analog.
POTS advantages and disadvantages • Advantages • Available everywhere • Reliable connectivity • Low cost • Easy setup • Disadvantages • Only one session per circuit • FCC limited transmission speed at 53 Kbps • Most circuits will only reach 44 Kbps due to line noise • Analog transmissions only
ISDN (Integrated Services, Digital Network) • A digitaltelephone service that works over copper telephone wiring • The three pieces of information to make your ISDN work with Windows-based PC • Switch type • Phone numbers • Service Profile Identifier (SPID) • Two ISDN interfaces • U Interface • S/T Interface
ISDN(cont) • Two “Rates”, Basic and Primary • Basic has 3 “channels”: • 2 “B” or “bearer” channels, to carry data • The B channels are 64 Kbps each. • 1 “D” or “delta” channel, to carry setup info • With the basic rate, the D channel is 16 Kbps. • Primary has 24 channels: • 23 B channels, at 64 Kbps each, and • 1 D channel, also at 64 Kbps (more bandwidth here because there is more info with primary) • A primary ISDN line has the same bandwidth as a T1 leased line.
ISDN • Integrated Services Digital Network (ISDN) turns the local loop into a TDM digital connection. • Usually requires a new circuit. • The connection uses 64 kbps bearer channels (B) for carrying voice or data and a signaling, delta channel (D) for call set-up and other purposes. • Never really became popular in the U.S., known as It-Still-Does-Nothing or I-Still-Don’t Know • See PPt #2 on ISDN
Activity A-1 Page 7-6 Discussing the features of POTS and ISDN
Cable Modems • Cable modems transfer data across local cable TV lines, toggling between analog and digital signals with data transfer ratescomparable to DSL.
Cable modems • CoaxialTV cable • 1 to 10 Mbps download speeds • Up to 2 Mbps upload speeds • Cable connects from NIC to a cable modem, which has an RJ-45 port • Many users connect a router to the cable modem to provide access to several PC’s or other network devices
xDSL • Family of technologies used for high speed, digital access over regular, copper telephone lines • Access speeds range from 1.544 (T1) to 8 Mbps for downstream data transfers and are around 1.5 Mbps for upstream data transfers • Note: The Network+ objectives just list “xDSL”; the only specific standard mentioned is ADSL.
xDSL and VDSL (I’m sure the RADSL upstream numbers should be “K”bps!) Two new additions to the category of dedicated connection: DSL Cable modems Very high bit-rate DSL (VDSL) is seen by many as the next step in providing a full home-communications / entertainment package. There are already some companies, such as Qwest that offer VDSL service in selected areas. VDSL provides an incredible amount of bandwidth, with speeds up to about 52 megabits per second (Mbps). 13
ADSL • Asymmetric DSL: The distinguishing characteristic of ADSL over other forms of DSL is that the volume of data flow is greater in one direction than the other, i.e. it is asymmetric. Providers usually market ADSL as a service for consumers to connect to the Internet in a relatively passive mode: able to use the higher speed direction for the "download" from the Internet but not needing to run servers that would require high speed in the other direction.
SDSL • Symmetric Digital Subscriber Line (SDSL) is a Digital Subscriber Line (DSL) variant with T1/E1-like data rates (72 to 2320 kbit/s). It runs over one pair of copper wires, with a maximum range of about 3 kilometers or 1.86 miles. The main difference between ADSL and SDSL is that SDSL has the same upstream data rate as downstream (symmetrical), whereas ADSL always has smaller upstream bandwidth (asymmetrical). However, unlike ADSL, it can't co-exist with a conventional voice service on the same pair as it takes over the entire bandwidth.
HDSL • HDSL (High bit-rate Digital Subscriber Line), one of the earliest forms of DSL, is used for wideband digital transmission within a corporate site and between the telephone company and a customer. The main characteristic of HDSL is that it is symmetrical: an equal amount of bandwidth is available in both directions. • HDSL can carry as much on a single wire of twisted-pair cable as can be carried on a T1 line (up to 1.544 Mbps) in North America or an E1line (up to 2.048 Mbps) in Europe over a somewhat longer range and is considered an alternative to a T1 or E1 connection.
IDSL • IDSL - “ISDN Digital Subscriber Line” transmits data digitally across existing ISDN lines, at a rate of 128 Kbps. The benefits of IDSL over ISDN are that the former service offers always-on connections, transmits data via a data network rather than the phone company’s voice network, and avoids per-call fees by being billed at a flat-rate.
RADSL • “Rate-adaptive” DSL - With RADSL the modem adjusts the upstream speed of the connection (in an upstream / downstream speed tradeoff) depending upon the length and quality of the line between the DCE (Telephone Exchange) or DSLAM and the DTE (Modem), in an attempt to maintain a certain downstream speed.
CDSL • CDSL (Consumer Digital Subscriber Line) is a version of Digital Subscriber Line (DSL) service, trademarked by Rockwell Corp., that is somewhat slower than Asymmetric DSL (ADSL) - up to 1 Mbpsdownstream, probably lessupstream - and has the advantage that a splitter does not need to be installed at the user's end. Rockwell no longer provides information about CDSL at its Web site and it does not appear to be marketing it.
Technology ADSL ADSL2 ADSL2+ HDSL HDSL2 IDSL MSDSL PDSL RADSL SDSL SHDSL UDSL VDSL VDSL2 ITU-standard ANSI T1.413 Issue 2ITU G.992.1 (G.DMT)ITU G.992.2 (G.Lite) ITU G.992.3/4ITU G.992.3 Annex JITU G.992.3 Annex ITU G.992.5ITU G.992.5 Annex M ITU G.991.1 ITU G.991.2 ITU G.993.1 ITU G.993.2 xDSL technologies
Satellite • Most practical for people who live in or travel to rural areas • Requires a dish mounted on the outside of a building • A clear view of the southern sky is also required • Weather and other atmospheric conditions can affect performance or cause interference
Wireless • Enables users to make a connection to the Internet while traveling or to the Internet or a LAN while freely moving about their house or office • Requires a wireless network card in the PC and a WAP to connect computers together or to connect to the Internet
Activity A-2 - Page 7-10 Discussing cable modem, xDSL, satellite and wireless access methods
Topic B page 7-11 • Topic A: Introduction to remote connectivity • Topic B: Installing and configuring a modem • Topic C: Remote Access Service (RAS) and remote access clients • Topic D: WAN connectivity
Installing an external modem • Use the Windows 2000/Server 2003/XPPhone and Modem Options utility
Phone and Modem Options dialog box • The “dialing rules” tab lets you add or edit locations. • Select a location, click “edit” and get the “Edit Location” box on the next slide.
Edit Location dialog box: • “General” lets you edit the location; • “Area Code” lets you config settings for calls to specific area codes, and • “Calling Card” lets you configure how to use a calling card from the modem.
Modems tab • The “modems” tab (from the 1st box, “Phone and Modem Options”) gives you a list of modems and lets you add (or remove) one.
Properties, General tab • The “General” tab gives you info on the device type, the manufacturer and the status of the modem (working properly?). • You can enable or disable the modem from here.
Modem properties, ‘Modem’ tab • Allows you to configure the port speed, speaker volume and whether to wait for a dial tone before dialing.
Modem properties, Diagnostics tab • Allows you to • enable logging, • view the log, • query the modem (to see how it is functioning).
Default preferences, General tab • Advancedtab of the Modem Properties pg then “Change Default Preferences” • General, to configure: • connection time • compression • flow control • other data control prefs • Advanced, to config: • data and stop bits • parity, and modulation
Other tabs you may see: • Power Management tab • Drivers tab
Modem error log • Once you enable logging, you can view the log by clicking “View Log” in the Diagnostics tab in the modem Properties dialog box.
Activity B-1 Page 7-18 Installing and configuring a new modem
Topic C page 7-20 • Topic A: Introduction to remote connectivity • Topic B: Installing and configuring a modem • Topic C: Remote Access Service (RAS) and remote access clients • Topic D: WAN connectivity
Enabling RRAS for dial-up connections • Management of RRAS is done with the Routing and Remote Access console available from the Administrative Tools menu • But, onlyon the “Server” OSs – Windows 2000 Server and Windows Server 2003. • The Routing and Remote Access Wizard is used to enable and configure RRAS for the first time
Dial-up protocols • For dial-up networking, you can configure • LANprotocols • TCP/IP • IPX/SPX • AppleTalk • Remote accessprotocols • Point-to-Point protocol (PPP) • Serial Line Internet Protocol (SLIP)
What are SLIP and PPP? • Two ways to connect personal computers to the Internet • Communications protocols • Software • Support for TCP/IP (Transmission Control Protocol/Internet Protocol) • Access to graphics and other file formats
What are SLIP and PPP? SLIP and PPP are protocols, or sets of rules, that support TCP/IP over serial cables such as telephone lines. (TCP/IP is the set of protocols used on the Internet). Therefore, SLIP and PPP are two ways to connect to the Internet. SLIP stands for Serial Line Internet Protocol and PPP stands for Point-to-Point Protocol. SLIP is the earlier technology; PPP is newer and has more capabilities. ----------------------------- [See the other Power Points on SLIP, PPP, WAN technologies in general, authentication with PAP and CHAP, etc.]
What are SLIP and PPP? SLIP/PPP allows a user with a PC, such as a Macintosh or a PC, and a modem to connect to the Internet, without having to first log on to a remote machine (but you do need an account). This capability enables the user to make use of Internet applications and tools such as telnet, file transfer (ftp), electronic mail, andgraphical web browsers directly on his or her personal computer.
What are SLIP and PPP? • A computer with a SLIP or PPP connection is able to simulate a direct connection to the Internet. To accomplish this, the user needs: • a computer and modem • a SLIP/PPP account with his or her Internet Service Provider • both SLIP/PPPsoftware and TCP/IPsoftware installed on the user's computer • an IP address - this may be permanently assigned to the user's computer by the provider or assigned "on the fly" at the time of the connection. The "on the fly" method allows service providers to support a large number of users with a limited pool of IP numbers.
What are SLIP and PPP? How does a SLIP/PPP connection work? 1. A user's modem dials up a remote computer at an Internet Service Provider (ISP). 2. The SLIP/PPP softwarerequests a SLIP/PPP connection. 3. Once the connection is made, the service provider assigns the user's computer an IP address (in the case of a service provider who assigns IP addresses "on the fly"). 4. The TCP/IP software on the user's computer "takes over" and manages the flow of data between the Internet and the user's computer.
Activity C-1 page 7-25 See PPt #3 on PPP (17 slides) then, Discussing RRAS
New Connection Wizard in Network Connections • Used to create dial-up connections • Gives mobile users the opportunity to work as if they are connected directly to the remote network • The speed of a dial-up connection will be much slower than a direct network connection