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INTERNETWORKING YOUR NETWARE LANS Connecting the PC Workgroup to the World (see press release at end of file, for latest update) The ability to connect independent networks is of key importance to any organization. This document looks at how organizations can evaluate their internetworking needs and how Novell products provide LAN-to-LAN solutions. As LAN technology has continued to evolve so have users expectations. Users realize that if sending an electronic file to a colleague down the hall is convenient, sending a file across the country will help productivity even more. If sharing a database among the staff in the corporate office simplifies and speeds order processing, sharing that same database with branch offices could streamline the entire order processing system. Novell recognized these needs early on, so over the past several years each new Novell product introduction has offered NetWare users increased levels of connectivity. NetWare products connect more than workgroups they also incorporate many workgroup networks into large Wide Area Networks (WANs). A Wide Area Network allows workstations on different LANs to transfer files, send electronic mail, access data files, and access applications on PCs, Macintoshes and host mainframes across the office, across the country and across the world. LAN-to-LAN Basics - Novell defines WANs in its broadest sense: a network connection or a series of connections that lets workstation users access remote resources including other LANs and mainframe hosts. LAN-to-LAN connections can be classified according to the type of transmission medium used to send the data. Services offered by telecommunications companies include point-to-point voice grade lines, packet switched services using X.25, and high speed synchronous lines including Digital Data Service (DDS) and T1 lines. Speedand cost are the primary factors that differentiate the transmission types. LAN-to-LAN connections are also classified according to the different data-link protocols that the network can accommodate. Some connections link LANs that share the same physical topology, data packet protocols and network operating system. Other connections incorporate LANs that differ in one or more of these aspects. LAN-to-LAN connection products provide hardware for connecting the LAN to the WAN and software to supervise the data transfer process. These products can be a special standalone box, or they can be an interface board that fits into a PC or file server and the associated software. Novell offers a family of LAN-to-LAN products to link workgroups via WANs: -NetWare Async Router -NetWare Link/X.25 -NetWare Link/64 -NetWare Link/T1 Defining the Level of LAN-to-LAN Connectivity - Since no two users are exactly alike in the way they use their PCs and other workstations, no two PC/workstation workgroups are exactly alike in their need for WAN connectivity. Each has its own needs expectations and resources. NetWare communication products accommodate the full range of WAN connectivity needs. The following seven questions will help evaluate the type of WAN connectivity a workgroup will need so you can choose the right level of connectivity. 1. What kind of work will be done across the WAN Link? 2. How much data will be transferred and how often? 3. How many sites must be connected and where are the located 4. What are the cost constraints? 5. What kind of technical expertise is available at the different sites? 6. How much growth will the system need to accommodate? 7. Overall, what services will the WAN Offer users? There are four kinds of WAN use. Each makes different demands on the WAN. Reviewing the needs of your workgroup in each of the four areas will help you estimate the volume of data that the WAN must support. What Kind of Work Will be Crossing the Link? FILE TRANSFER: File transfers usually place relatively little strain on the network. Sending a file between workstations or between the workstation and the file server involves only one way communication. The sending workstation can complete the transaction without waiting for a reply from the receiving workstation hence no realtime interaction between the two stations is needed. However, if the network is busy and the file is very large, the file transfer may take several hours for the data transmission to occur. ELECTRONIC MAIL: Electronic mail systems allow users to transfer memos and documents from one workstation to another. Time is not usually a factor. Once a mail message has been sent the user's workstation is available immediately to perform other activities--mail is expected to be delivered in a few minutes or hours. Again, without real time interaction between the workstations the load placed on the network is light. If the electronic mail system is used extensively, however, some systems can get sluggish. REMOTE APPLICATION USE: The use of an application which resides on a file server on the other side of the link puts a very heavy load on the WAN as the entire operational kernel of the application must be uploaded by the local PC. In addition, many applications assume that access to the file server will be almost instantaneous and swap portions of the program between the drive and the PC every few minutes. With most applications this makes the use of anything slower than a T1 line impractical even then, program operation can seem slow. However, careful planning can frequently avoid this situation and if not, the NetWare Access described below is an attractive alternative. Novell has developed special server products, including the NetWare SQL Database, that reduce the amount of data that is sent across the WAN during data base use. HOST ACCESS: A workstation can act as a terminal for accessing applications on a remote mainframe. Terminal emulation requires a moderate level of interaction between the workstation and the host. The terminal must communicate with the host in real time, but since both the application and the data file are on the host computer, the volume of data being transferred is small compared to remote application use. How Much Data Will be Transferred and How Often? - In each of the above, the volume and frequency of data transfer have a direct impact on the type of LAN-to-linkneeded. For instance, even though remote application use is slow over a DDS line, if usage is light and access is infrequent and the application small a DDS line may be adequate. On the other hand if the company only sends electronic mail over the network, but does so frequently and the users number in the ten thousands a T1 line will be necessary to address the volume. The following table gives some rules of thumb for determining the type of transmission medium most appropriate for different types of use. The table compares three types of lines: voice grade telephone or X.25 lines, which transfer data at up to 19.2 kbits/s: DDS lines which can go up to 56 kbit/s, (USA) and 64 kbits/s (Europe) and t1 LINES AT 1.544 mBITS/S (USA) and CEPT lines at 2.048 Mbit/s (Europe). As the frequency, volume, and complexity of data transfer go up the type of line used to carry the data requires greater speeds. Voice or X.25 DDS T1 <=19 2 kbts 56 kbits 1.5 Mbits(USA) 64 kbits 2.0 Mbits ------------------------------------------------------------------- File Transfer Yes Yes Yes Simultaneous Sess. 1.3 3.8 75 ------------------------------------------------------------------- Electronic Mail Yes Yes Yes Number of Users 500 <3,000 No Limit Simultaneous Sess. N/A N/A ------------------------------------------------------------------- Remote Application Use No Very Slow Adequate ------------------------------------------------------------------- Host Access Yes Yes Yes Simultaneous Sess. 16 64 1,000 ------------------------------------------------------------------- What Kind of Sites Must be Connected and Where are They Located? - The number of possible variations is almost infinite. Here are 3 common types: 1. Central Hub With Branch Offices - Each branch office could be connected to headquarters by a link with no direct connection between the branches. This configuration can often use voice grade lines but, in heavy traffic situations, it can benefit from high speed DDS connections. 2. Several Regional Hubs - It is likely that each regional hub would like to be directly connected to every other regional hub. This type of configuration requires that the systems analyst give some thought as to which remote sites need to communicate with each other. It can be expensive to give everyone on the network equal access to everyone else, and it usually isn't necessary. A voice grade or DDS synchronous connections can be used to connect the branch offices to the hubs and DDS or T1 synchronous connections to connect the regional hubs with the home office. 3. Two Major Sites - If two major sites would like to share data as if they were one large site a substantial volume of data would have to pass through a central WAN backbone. If the traffic was fairly light the WAN could be based on DDS lines. However, even moderately high volume situations would benefit from a T1 or fractional T1 line. What are the Cost Constraints? - Many companies would like to provide all the communication and data sharing resources that are available. In practice, however, the cost of hardware and telecommunications company charges force the systems analyst to set priorities. Many users are used to sending and receiving data at 2400 baud expect 19.2kbits or 56kbits to provide almost instant transfer of data. However, LAN-to-LAN connections are used for more demanding tasks than access to a BBS or a service such as CompuServe and require fast transmission speeds for even moderate levels of volume. Voice or X.25 DDS T1 <=19.2 kbts 56 kbits 1.5 Mbits(USA) 64 kbits 2.0 Mbits Line Installation $100 $300 $2,500 Monthly Rent $20+ $90-500+ $300-2,600+ $3 per mile $6 per mile $14 per mile $/Month for 500 miles $100 $3,000 $9600 (The $ will vary with vendor, place, time, and volume) Many companies have T1 lines installed already for voice communications. One WAN connectivity option is to use one channel of the line for data in order to evaluate whether a dedicated T1 line for data communications is necessary. The cost of installing a LAN-to-LAN link is offset by the increased productivity of people who communicate better and the savings in other types of communications services such as facsimile express courier and voice. How Much Technical Support is Available at Different Sites? - An asynchronous connection which uses voice grade phone lines with a remote product (like ONLAN which comes with NetWare Access Server) requires almost no system maintenance at the branch office site. For a branch office with no computer support staff, this is very important. At the other end of the spectrum a wide area network connecting two major sites, many minor sites dozens of file servers and thousands of workstations requires an entire systems maintenance department. Most wide area network sites fall in between these two extremes. Part of the decision to implement a wide area network involves the allocation of technical support personnel. In some cases, even though a 56 to 64kbit/s X.25 synchronous line might increase the speed of data transmission, the additional cost of supporting the X.25 link located at the remote site does not justify moving from the voice grade line to the X.25 line. In other cases the increased ability to communicate and share data more than offsets the cost of technical personnel. How Flexible Does The System Need To Be? - A flexible system is easily upgraded or changed. LANS and other resources can be added and deleted without major disruptions. A flexible system also means that as users needs change users can get the information they need without a great deal of extra expense. Setting up inexpensive point-to-point voice grade connections can be a good way to get started but the system can get very complex if the company connects a large number of branch offices without ever establishing central or regional hubs for information sharing. As more connections are required, what started as an easy solution becomes complex and difficult to maintain as point-to-point voice grade connections are no longer adequate. At this point a WAN backbone may be needed. Some extra expense in the beginning establishing a flexible system based on WAN backbone can pay off in the long run for organizations whose systems are bound to grow. Establishing regional hubs and a simple topology offers increased flexibility. Existing workstations can be given new access rights new workstations can be added to a LAN and new LANs can be added to the wide area network. As your network continues to expand, however, point-to-point connections centered around regional hubs may become too complicated to manage. As a next phase of WAN development you may need a network service to manage the virtual connections on the WAN for you. Then if the surcharges for relying on such a service become too high, it may be more cost effective to set up your own private data network to manage your WAN connections. What are the Overall Goals of the Network? - Defining the goals of the WAN system is critical not only to the success of the system but to its cost effectiveness and ability to accommodate change and growth. Ultimately, the configuration of the wide area network needs to reflect the goals of the organization as a whole. Perhaps the engineers would be more in touch with the needs of the marketplace if there were an E-mail system connecting the sales force and the engineers. or maybe orders could be filled faster if there were a direct DDS line from a regional office to the corporate headquarters so sales personnel could enter orders directly int the corporate mainframe. Since it is often too expensive to connect everybody to everybody else for all types of data transfer the system needs to reflect the strategic decisions made at the top management level. After looking at all of these questions the analyst has a good profile of projected system and some of the constraints involved. The next step is to look at the Novell solutions. NOVELL SOLUTIONS Point-to-Point voice grade lines - To connect LANs over voice grade telephone lines, Novell offers the NetWare Async Router. The Async Router is commonly used to connect branch offices to a regional hub or home office and with a WNIM board can support speeds up to 19.2kbit/s. Multipoint X.25 Connections - NetWare LINK/X.25 allows multiple connections at up to 64kbit/s via an X.25 packet switching network. In the latter case, each regional office needs only a line into the nearest public data network (PDN) node saving long distance telecommunications charges. The PDN system then takes care of routing the data to the destination site. This type of link offers the advantage of flexibility without additional network management. Link/X.25 is designed for use in PDN based multipoint wide area networks. High Speed Point-to-Point Connections - Novell offers two high speed LAN-to-LAN products for internetworking, LINK/64 and Link/T1. Link/64 is a cost effective solution for those who expect their LAN-to-LAN connection speeds to remain at 64kbit/s and below, while LINK/T1 offers a high performance solution for the full range of data transmission speeds from 9.6 kbit/s to 2 Mbit/s. LINK/64 offers the same functionality as LINK/T1 but at a reduced maximum data rate. Link/T1 is designed to be used in high volume situations to connect remote hubs. The LINK/T1 connections can become a high-speed WAN backbone supporting a variety of configurations for home, regional and branch office. A Different Method - Much of the functionality of a WAN can be attained by instead using a NetWare Access Server connected to a NetWare LAN. Each Access Server can be used to provide up to 16 connections and 16 DOS session to remote sites. The connections can be through individual dial up lines, multiplexers, X.25 service, or via IPX across a synchronous line. In each case, because Access Server only requires keystrokes and screen updates to cross the lines an acceptable rate of speed can be attained for a lower line cost than a straight WAN solution. In particular, it makes "remote application use" feasible in situations that would otherwise require a T1 line. FOR FURTHER INFORMATION In Netwire Library 9 (communications) - TN6RUL.TXT for the "Rules of Thumb" for LINK/64 and LINK/T1. - ARORUL.TXT for the "Rules of Thumb" for the Asynch Router. - ACERU2.TXT for the "Rules of Thumb" for Access Server Call 800-NETWARE and ask for "Communications Product Information". ----------------------------- FOR IMMEDIATE RELEASE: Novell Announces Release of WAN Links v2.0 Product Simplifies WANs, Supports More Protocols, Extends 3rd Party Support, and Consolidates Functionality SAN JOSE, Calif., -- August 3, 1992 -- Novell today announced an expansion of its enterprise networking capabilities with the introduction of NetWare WAN Links v2.0, enabling the routing of IPX, TCP/IP, AppleTalk and OSI traffic across X.25-based public networks or private networks based on leased lines. NetWare WAN Links v2.0 simplifies the implementation and management of wide area networks by building on end users' and resellers' knowledge of NetWare. The familiar NetWare interface is integrated into the improved configuration and installation utility. WAN Links works with a dedicated NetWare MultiProtocol Router in a corporate headquarters environment with high-traffic demands or with a NetWare server in a branch office with less intense traffic. Novell's internetworking strategy is built on using standard off-the-shelf PCs, making enterprise networking easy and economical. In a related move targeted to encourage third parties to develop WAN cards for the NetWare WAN Links v2.0 environment, Novell also announced the Wide Area Network Interface Specification (WANIS). WANIS defines the programming interfaces for developers who wish to incorporate their wide area links such as Frame Relay, SMDS or ISDN WAN cards, into a NetWare MultiProtocol Router or NetWare server. "NetWare WAN Links v2.0 allows customers to connect geographically dispersed LANs in a multiprotocol environment easily and inexpensively," said Navindra Jain, vice president and general manager of Novell's Internetworking Products Division. "With WANIS, Novell is opening its wide area networking interface to third-party developers thereby providing customers more choices of products that operate and are managed in a uniform manner." Announcement Highlights Highlights of the NetWare WAN Links announcement are: Enhanced and combined functionality of previous Link products into one Routing of IPX, TCP/IP, AppleTalk, and OSI over wide area links (Previously Novell could only route IPX over wide area links.) Support for Point-to-Point Protocol (PPP), the IETF standard for multivendor/multiprotocol environments Support for X.25 Improved SNMP management capability WANIS availability to third-party vendors that allows them to easily develop compatible products. Product Consolidates Former Offerings NetWare WAN Links v2.0 combines and improves upon the functionality offered in previous link products including Link/64 v1.1 and Link/T1 v 1.1. In addition, WAN Links 2.0 includes support for X.25, allowing users to access public and private X.25 data networks. PPP and X.25 Support Point-to-Point (PPP) is designed to provide vendor interoperability by defining a standard for running multiple network-level protocols, such as IPX, TCP/IP and AppleTalk, over serial wide area network links. With PPP, users can directly interconnect one manufacturer's router to another, such as a NetWare router to a Cisco router in an IP environment, via high speed serial lines. PPP leverages a customer's existing investment in routers. Link/X.25 provides services for NetWare products and other applications requiring wide-area connectivity to public and private X.25 networks. The X.25 configuration utility features a set of Novell-developed profiles for the major X.25 public data networks that significantly simplifies the configuration process. Network Management Features Novell's internetworking products support the industry standard for network management, Simple Network Management Protocol, SNMP. More importantly, Novell is providing a way for third parties to connect to the network management environment. The benefit is a single network management interface for the end user. Novell's SNMP agent supports TCP/IP and IPX protocols. In addition, the extensible SNMP agent allows third party developers of WAN cards to interface their MIBs into the NetWare environment. Customers can manage their wide area links remotely. In addition to traditional IPX-based remote console utilities, Telnet and X-Windows support have been added to allow for remote management from TCP/IP and UNIX workstations. WAN Links provides access to a DSU/CSU supervisory port for management that makes trouble-shooting possible from any workstation on the network. Wide Area Network Interface Specification (WANIS) WANIS is being distributed to encourage the growth of network computing over wide area links. The specification extends the concept of Novell's Open Data Link Interface to the wide area environment. WANIS allows developers to more quickly and easily integrate their WAN adapters with the NetWare MultiProtocol Router, NetWare, or NetWare for SAA. WANIS also shields end-users from having to learn separate installation and configuration utilities for each manufacturer's adapters. "WANIS is a step forward in the integration of networks and eases the task of third-party developers," commented Larry Stephenson, President, Newport Systems. "Newport Systems will port all our LAN 2 LAN wide area network products, such as X.25 and Frame Relay, to the WANIS interface." Pricing, Upgrades, Availability and Educational Seminars NetWare WAN Links v2.0 has a suggested list price of $1295 (U.S.), if purchased between now and October 31, 1992. After that date the product will have a suggested list price of $1495 (U.S.). NetWare WAN Links v2.0 will ship in September and will be available through Novell authorized resellers. There are two upgrade paths from previous versions of NetWare Link products to the new NetWare WAN Links v2.0. If NetWare Link/64 v1.1 or Link/T1 v1.1 was purchased between June 1, 1992 and July 31, 1992, the customer is eligible for a FREE upgrade to WAN Links v2.0. The customer must request the free upgrade by calling 1 (800) UPDATE-1 on or before October 31, 1992. If Link/64 or /T1 v1.1 was purchased prior to June 1, 1992, or if the customer wishes to upgrade from Link/64 or /T1 v1.0 to WAN Links v2.0, the suggested list price is $625 (U.S.). For pricing outside the U.S. and Canada, customers should contact their local Novell reseller. To educate customers and resellers on this new, multi-purpose platform approach to building manageable internets, Novell, Intel and WilTel (a leading provider of leased line services) will conduct a series of FREE seminars beginning September 2, 1992 and concluding October 20, 1992. The seminars are scheduled for the following cities: Santa Ana, Sacramento, Los Angeles, Seattle, Phoenix, St. Louis, Dallas, Minneapolis, Chicago, Detroit, Philadelphia, Boston, Herndon (VA.), Atlanta, Toronto and New York City. For more details, please call 1 (800) 231-2000, extension 353. Novell, Inc. (NASDAQ: NOVL) is an operating system software company, the developer of network services, specialized and general purpose operating system software products including NetWare and DR DOS. Novell's NetWare network computing products manage and control the sharing of services, data and applications among computer workgroups, departmental networks and business-wide information systems.