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e -server magazine

May 1997: Volume 12, Number 5


Infinite Internet Networking

By Joan Burek

emember when food, shelter and clothing were the only three requirements necessary to support humanity. Well, make room for the fourth, ‘cause the Internet has arrived, and absolutely everybody needs it! Your end users, boss, suppliers, clients, practically everyone your company deals with, both internally and externally, need it for e-mail, EDI (electronic data interchange), JIT (just in time inventory), electronic commerce, distance learning, competitive information, market studies, and so on.

But – you have a network. A network that was designed to support your mission critical applications. Could it be possible? Could your network be extended to support this new requirement without major heartache, conversion or manipulation?

Well, if your network is called Frame Relay, you can leverage your existing high speed infrastructure and access the Internet now.

We don’t mean to ignore X.25, but realistically, X.25 just doesn’t cut it when it comes to the Internet. X.25 is painstakingly slow when compared to Frame Relay, and guaranteed to annoy even the most patient Internet user, particularly if the user is transmitting/receiving standard Internet-type images and files (read: large). The table below identifies X.25’s weaknesses against Frame Relay for the “large file transfer” application.

So How Do You Do It?

You do it with your network provider! Your network provider may offer Internet services that merge your current network high-speed infrastructure with the Internet. And your advantages ...

It is important to note that multi-purpose networks, or those that serve both “mainframe/mission-critical” and Internet-based applications, must provide sufficient bandwidth for both accesses. While individual subscriber e-mail and browsing requirements vary greatly, an initial additional 4K CIR (Committed Information Rate), for both inbound and outbound Frame paths, should be allocated for every 10-25 subscribers. Your subscribers’ individual usage will dictate whether this allocation is sufficient, over- or underkill. The network provider kit-bag of Internet options should include:  Figure 1. Subscriber Services Flow

SUBSCRIBER SERVICES

For smaller companies with a limited number of “id’s”, subscriber services provide individual Internet id assignment for corporate and remote users. This individual ‘company’ id, assigned and maintained by network provider, permits wide area access to Internet e-mail and browser applications. The network provider hosts all customer e-mail, via an assigned host name or through a virtual domain, such as the customer’s current Internet address (i.e. customer.com/.ca). Each subscriber would access the network provider’s mail host to access their e-mail.

Subscriber Services Flow

(Figure 1.)

“1” notes the path between the Internet and the network provider’s Firewall / Server and its subscriber e-mail database. “2” notes the path from the Firewall / Server (and its subscriber e-mail database) to network provider’s Master Switch. “3” notes the path, via the Frame Relay network, from the Master Switch to the subscriber connection. “3a” refers to the mainframe or head office locations and “3b” refers to the remote user location.

As noted in “1”, Internet ‘mail’ is received from the Internet by the Firewall/Server, and stored in the subscriber e-mail database. When the individual subscriber requests mail retrieval, as noted in “3a” and “3b”, the requests flow to the Master Switch, which are routed to the Firewall/Server (via “2”) subscriber e-mail database. E-mail is stored in the network provider’s subscriber e-mail database until retrieved by the individual subscriber. Web browsings’ route is from the individual subscriber (‘3a’ or ‘3b’), through the Frame Relay network, to the Master Switch, through the Firewall/Server, to the Internet. All non-Internet, mission-critical applications flow, bi-directionally, between the ‘mainframe’ and the remote sites.  Figure 2. Gateway Services Flow

GATEWAY SERVICES

In addition to Internet browsing, Gateway services provide corporate e-mail forwarding from the Internet to the corporate SMTP gateway. This service is ideal for:

The corporate domain is hosted on the network provider’s host, however, the subscribing company is responsible for providing the SMTP gateway.

Gateway Services Flow

(Figure 2.)

“1” notes the path between the Internet and the network provider’s Firewall / Server and its gateway e-mail database. “2” notes the path from the Firewall / Server (and its gateway e-mail database) to the network provider’s Master Switch. “3” notes the path, via Frame Relay, from the Master Switch to the client “mainframe” SMTP gateway. The client’s SMTP gateway serves as the focal point for all e-mail and Internet inquires/responses. “4” notes the destination for all corporate user Internet e-mail requests and responses. As noted in “1”, Internet ‘mail’ is received from the Internet by the Firewall/Server, and immediately transferred to the client’s SMTP gateway, via the Master Switch and the Frame Relay network. The remote client requests mail, via the Frame Relay network (#4), from the corporate mail service (SMTP gateway). Web browsings’ route is from the individual subscribers (#4), through the Frame Relay network, to the client gateway (#3), to the Master Switch, through the Firewall/Server, to the Internet (#2 & #1). All non-Internet, mission-critical applications flow, bi-directionally, between the ‘mainframe’ and the remote sites.

CORPORATE WEB SERVICES

Corporate web services permit the hosting of the company’s web site on the network provider’s host system. A virtual domain, per company, and directory structure is accessible by each subscribing company. Your network provider may also offer professional Web development services to assist in the development and enhancement of the Internet site.

Individual Internet services will differ per network provider. However, your Frame network’s flexibility and accessibility, beyond your ‘mission critical’ routes are your map to Internet success. So what are you waiting for, call your network provider today! T < G