Host Connectivity via The Internet
Historically client-host connectivity requires a direct connection to the host via LAN, WAN or modem and a client terminal emulation software or controller with dumb terminal. The telecom costs are considerable for each client station or LAN requires an individual, private connection. Maintenance is also costly because each client must have a software emulator installed locally. Ongoing maintenance issues, such as varying hardware compatibility, system crashes and additional installation, must be factored in. A TCO of this type of delivery can be seen in Table 1.
Host router port per client (fixed) $1,000 (typical)
Host telecom connection (monthly) $500 (typical)
Client router (fixed) $1,200 (typical)
Client router install $1,000 (typical)
Client telecom (monthly) $500 (typical)
Client software license $189/seat (typical)
Client software installation $100/seat (typical)
Client maintenance (monthly) $250 (typical – 10 user site)
Table 1: LAN Scenario
Therefore, for a LAN site with app. 10 users it can be seen that typical costs are: Fixed: $6,090 and Monthly: $1,250. Multiply this by each remote site and you can see how costs and maintenance rapidly increase.
By using the Internet as preferred WAN network and incorporating an Active X or Java emulation applet, costs on all fronts may be reduced substantially while same functionality and security is maintained (See Table 2).
Host router to internet (fixed) $1,200
Host telecom (monthly) $1,000
Host gateway server (fixed) Approx. $17,000 (includes all required software)
System Integration (fixed) $8,000 to $12,000
Client router $ not required
Client software $ not required (uses Internet Explorer or Netscape)
Client installation $ not required (self installing applet)
Client maintenance $ not required
Client telecom $ can be either dedicated or dial-up to local provider
Table 2: Internet Scenario
The single host connection in this scenario provides host services to ALL clients. Clients require no on-site technician visit as they may use their existing Internet connection and the host gateway server centrally distributes all software. All updates are automatic and host maintains complete control over "look and feel." Redundancy for connections is far easier to implement and much less costly – so reliability is far better than either point-to-point or private frame relay.
Additional Features. Include combining Web content with host session for increased client usability; and single point maintenance for all software; and the ability to incorporate total graphical interface to host data, no more "green screen."
Implementation. BAI Systems has implemented this scenario using the following hardware and software:
-NT Server capable of operating as a robust http: and SNA server. Typically a P-233 with 128mb ram and 3.0g disk storage can easily provide 128 simultaneous host sessions and many more Web only sessions.
-Microsoft NT Server 4.0 with IIS 3.0 or IIS 4.0
-Microsoft SNA Server 3.0 or 4.0
-Farabi Host Front to provide host session capability
-Farabi Host Front Publishing to provide server side scripting (enables dynamic html generation of host data)
-Dedicated Internet connection via frame-relay or similar
-Ethernet adapter or similar connection available on host server
Security. The NT gateway server using SNA server acts as a natural firewall preventing any direct attack to the host via Internet or intranet. Also, since TCP/IP is NOT required on the host, performance of the host is not affected.
Farabi Host Front incorporates it’s own authentication outside of standard NT domain security and provides for encrypted data transmission. IIS or similar web servers also provide for data encryption based on the https: protocols. By using Host Front Publishing it is possible to expose ONLY those data fields required for query or entry and further restrict user functionality. Also – since the host sessions are controlled totally by the host front server, hours of operation, client exclusions and session availability may be more easily monitored and controlled.
Availability. Farabi Host Front or comparable Web-to-host software, Microsoft SNA Server and IIS are proven, mature enterprise ready solutions. Many Fortune 1000 companies are now using host – Internet gateways to provide their remote clients unequalled functionality and solid day to day reliability.
Comparison. This will assume 30 client sites connecting to one manufacturer’s AS/400 or Mainframe. Typical Router to Host Via Dedicated 56K Solution: Excluding Site specific Server setup i.e. SAA or SNA Server Connected to Host system. Total hardware/software routers cost: $6090 per 10 user LAN X 30 = $182,700 fixed; Total monthly maintenance cost software upgrades/Telco charges and router maintenace, $1250 Per 10 user LAN x 30 = $37,500 per month.
Web-to-Host Connectivity. Including Total Site specific Server setup with SNA Server and Internet host connectivity software connecting to AS/400 or Mainframe. Total hardware/software routers: Internet router at manufacturer, $1200; Fully configured NT Sever with Internet host connectivity software including system integration and Web design, $25,000 (fixed one time cost).
Monthly. Dedicated Frame Relay Connection to the Internet $1000 or less, depending on bandwidth.
Note: No client side software router or dedicated phone line needed only a connection to the Internet ($19.95 a month), now your MIS department has more time to focus on site specific issues, like the Year 2000.
ABOUT THE AUTHORS:
Tim Smith is President of BAI Systems (Sausalito, Calif.) with over 10 years experience as a systems engineer working in AS/400 and mainframe environments containing Novell, NT, SAA, SNA Server and Farabi Technology’s Host Front.
John Siska is Vice President of BAI Systems and has over five years experience in Sales/Marketing Project Management with in LAN and WAN environments containing Legacy systems.
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