The events of Sept. 11 crippled Internet and telephone service in and out of New York City during a critical time for friends and family. Earlier this year, the collapse of digital subscriber line providers Northpoint Communications and Rhythms NetConnections left more than 100,000 customers stranded.

And, just last week, the bankruptcy of At Home Corp. severed service to 850,000 cable Internet subscribers - including thousands of families and small businesses in the Dallas area.

As Internet connectivity has moved toward becoming a vital utility of modern life, so has the need for backup plans in the face of communications disasters.

"The Internet itself was set up to route around blockages; it's almost like consumers have now got to think in the same way," said Steve Linebarger, president of Texas Metronet, a local Internet service provider. "It's getting real important to have more than one way to make connections."

For many, the sudden loss of home and small business Internet communications induced a frantic reaction.

"I've been calling ISPs all day, trying to convince them I just need a dial-up connection until AT&T gets its act together," said Jim Leahy of North Dallas, a work-at-home salesman who relied on the Excite@Home cable service for daily work correspondence. "I guess I never really believed they would just drop us like that. I had no idea what to do, but I was losing money every minute."

Internet professionals, networking gurus and disaster preparedness experts offer some practical advice for Mr. Leahy and others blindsided by network outages.

"In times like these, it pays to think creatively," said Fran Jenison, president of Cynon Computers Networking, a computer networking consultancy based in Houston. "And it really pays off if you've developed a foolproof contingency plan to get back up and running quickly."

Not all solutions will work for every small business or home computer user.

Some require monthly cash outlays that may seem exorbitant to casual Internet users. But to anyone who relies on Internet connectivity and e-mail correspondence for daily routines, many of these suggestions by experts may prove invaluable in times of communications disasters.

Mr. Linebarger said his medium-sized ISP received calls from 10 to 20 percent of his customers who dropped monthly, $16 dial-up accounts lately as they migrated to faster cable and DSL service.

Keep a dial-up option

"They all wanted $5 dial-up accounts temporarily, and we just don't have any pricing options like that," he said. "If I thought this would be an ongoing problem, we'd come up with a pricing alternative."

For reliable backup Internet connectivity at the cheapest price, it may be best to investigate the lowest-tier options available from national ISPs such as AOL, Earthlink and Compuserve, he said. All three currently offer base service at $4.95 to $9.95 per month. Those plans carry hourly charges of $2.50 or more above a certain threshold, so heavy use during an extended outage may be costly.

"Still," said communications disaster consultant Frank Mahew with Reliable Communications of Des Moines, Iowa, "any connection is better than no connection in times like that."

He said home and small office users often discard or sell their dial-up 56 kbps modems after signing on with broadband services. "That's just not smart," he said. "Hold onto those modems. They may be your lifeline, as many people are finding out now the hard way."

E-mail escape routes

Before an outage disrupts life, create a Web-based e-mail account on one of the free services available from portals such as Yahoo (www.yahoo.com) and MSN (www.hotmail.com), Ms. Jenison advises.

"Web-based accounts - accounts that are independent of your broadband provider's network - are accessible no matter where you are in the world," she said. "They make sense to maintain as backups, especially since they're free."

Most can be configured to pull down mail from other accounts vital to business and family communications.

"Many times, you'll find they can access e-mail servers when the rest of the network is in a shambles," Ms. Jenison said. "Your Internet access may be down, but the mail servers are often running on separate lines that can stay open and functional."

In the case of the Excite@Home outage, any e-mail that ended with @home.com was held hostage. The company refused to migrate existing accounts to the new @attbi .com addresses unless AT&T paid additional fees. When AT&T balked, subscribers were left with bouncing e-mail and no access.

By planning for outages, users could have avoided a complete communications collapse by storing their address books inside one of the free, Web-based alternatives.

AOL offers AOL By Phone for a fee, but Yahoo and Lycos have both launched voice-powered portals that allow subscribers to retrieve e-mail by telephone.

"When you can't get on the Net," Mr. Mayhew said, "having your mail read to you over a cellphone isn't a bad little fallback."

And, if phones are jammed during a disaster such as the terrorist strikes in New York and Washington, free Internet voice services like Yahoo Messenger can prove invaluable.

Voice over IP connections require the two parties to be correctly outfitted with microphones, sound cards and compatible software, so planning for emergencies is again imperative.

If friends, family and business connections are all set up with the same instant messaging software, contact can often be made during times of communications crisis when telephones fail, experts say.

They may be pricey, but Web-enabled cellphones and wireless Web services from companies such as Sprint PCS and VoiceStream may prove a salvation when routine Internet connectivity is disrupted, experts say.

"Those services aren't cheap, but the wireless stuff is getting more and more dependable - even in times of crisis," Ms. Jenison said.