DUX COMPUTER DIGEST

 

Site Search

Site Info

Home » Forums » Forum Archives » Networking and Internet Sharing » Topic # 1137

Notebook connected to Cable and DSL...?
Accessdabbler Aug-22-01 07:46 PM
I have a notebook computer. At work, it will connect to a Cable modem (through a hub).

At home, I have DSL. I do not have a network setup at home... yet.

Question: How can I setup my home network so that my Notebook can share EITHER the cable or DSL modems?

Further complications: At work, WinGate is used to share the cable modem. My notebook is setup as a WinGate client.

Options: As I am the owner at work, I can juggle the network settings if required.

Ideally, I come home from work, plug in my notebook to the home network and begin surfing without having to fiddle with settings on my notebook. Am I dreaming?


1. RE: Notebook connected to Cable and DSL...?
lbyard Aug-23-01 12:49 PM
In response to message 0
Are you runnng Windows 9x/Me or NT/2000? Larry

2. RE: Notebook connected to Cable and DSL...?
Accessdabbler Aug-23-01 01:17 PM
In response to message 1
I have Windows 98 on the notebook.

Yes, I can try ICS but at home I plan to access the internet through a router to avoid having to turn on the main home computer when I want internet access.

I am considering putting a router in at work so that one of the computers does not act as the internet server.

(by the way, what is the difference between a hub and a router? Can a hub replace a router for a small network using the internet?)


3. RE: Notebook connected to Cable and DSL...?
lbyard Aug-23-01 06:18 PM
In response to message 2
I would put a router in both locations. Cost about $100/each. Good questions… Here are some answers--perhaps more than you bargained for. Larry

Q. What are the differences between an Ethernet hub or switch and a broadband router?

A. For an introduction to Ethernet hubs and switches and their differences, see “What is the difference between an Ethernet hub and switch?” at http://duxcw.com/faq/network/hubsw.htm.
Most broadband routers (“routers” for short) are a combination Ethernet switch (or hub) and Network Address Translator (NAT; see below). They usually include a Dynamic Host Configuration Protocol (DHCP) server (http://www.intel.com/support/landesk/configmgr/23099.htm#1), Domain Name Service (DNS) proxy server (see below), and a hardware firewall to protect the Local Area Network (LAN) from malicious intrusion from the Internet.
All routers have a Wide Area Network (WAN) Port. This port connects to the to a DSL or cable MODEM for broadband service (e.g., the Internet) and is usually a 10 MHz 10BASET Ethernet port. A 10 MHz WAN port is sufficient for cable and DSL MODEMs as these devices transfer data at rate that is a fraction of 10 MHz. I have seen no broadband routers with a USB WAN port to connect to a USB cable or DSL MODEM.
Many recent broadband routers are combination routers/Ethernet switch (or hub) that have multiple Ethernet ports to connect more than one PC to form a LAN. These ports allow the PCs to share the WAN port/broadband Internet connection and perform LAN functions, such as Windows file and printer sharing. The LAN ports are usually 100 MHz 100 BASE-TX Ethernet.
Some routers have a single WAN port and a single LAN port and are designed to connect to an existing LAN hub or switch to a WAN.
Ethernet switches and hubs can be connected to router with multiple PC ports to expand a LAN. Depending on the capabilities (kinds of available ports) of the router and the switches or hubs, the connection between the router and switches/hubs may require straight-thru or crossover cables (http://duxcw.com/digest/Howto/network/cable/cable1.htm). See “What is an uplink port and what are the ways to connect two hubs/switches together?” at http://duxcw.com/faq/network/uplink.htm for details.
Some routers have ports for USB connections to computers on a LAN. Some have wireless LAN capabilities.
In addition to a WAN port, broadband routers, such as the SMC Barricade routers (http://duxcw.com/digest/Reviews/Network/smc/smc7004br/smc7004br.htm), may have a serial port that can be connected to an external dial-up MODEM (useful as a backup for the cable of DSL service) and a built in LAN printer server and printer port.
A router DHCP server provides local Internet Protocol (IP) Addresses (http://support.microsoft.com/support/kb/articles/Q164/0/15.asp; e.g., 192.168.02, 192.168,.0.2,…) to PC’s, etc. on the LAN set to obtain their IP addresses automatically. Tjhese DHCP servers can usually be configured to allow assignment of static IP addresses to PCs and other devices on the LAN. A router-borne DNS proxy handles Internet name resolution requests form PCs on the LAN to the ISPs DNS servers to translate names of computers on the Internet to IP addresses (e.g., duxcw.com to 216.92.56.121). The NAT function in the broadband router allows sharing a single IP address provided by the Internet Service Provider with PCs connected directly to the router/switch or to hub or switch connected to the router by mapping local LAN IP addresses (assigned by the DHCP server or static IPs on the same TCP/IP subnet) to Internet IP addresses and vice versa and translating the address information in the TCP/IP protocol packets.
Besides the inherent protection features provided by the NAT, many routers have a built-in, configurable, hardware-based firewall. Firewall capabilities can range from the very basic to quite sophisticated. Among the capabilities found on leading routers are those that permit configuring TCP/UDP ports (http://www.iana.org/assignments/port-numbers) for games, chat services, and the like, and installing web servers, etc. on the LAN behind the firewall.
In short, a hub glues together an Ethernet network segment, a switch can connect multiple Ethernet segments, and a router can do those functions plus route TCP/IP packets between multiple PCs on LAN and a WAN, and much more.

Q. Can a hub replace a router for a small network using the internet?

A. Qualified no—mostly no. You could use a hub to connect PCs to a cable or DSL MODEM if you want to pay your service provider a monthly fee for an IP address for each PC.

Q. What are the ways to share a broadband (cable or DSL MODEM) Internet connection?
A. There are few ways to do it. One is to purchase another IP address from your service provider. Most service providers charge a monthly fee for additional IPs. The best way is to purchase a broadband router such as the SMC Barricade (http://duxcw.com/digest/Reviews/Network/smc/smc7004br/smc7004br.htm). That is what I use. They cost about $100.
The Barricade has serial port for an external dial-up MODEM and a printer port and printer server. A printer can be connected to the Barricade and shared by computers on the local network. Not all printers will work with it. Many routers do not accommodate an Internet connection via an external dial-up MODEM and do not have printer port and server.
The Barricade can be connected to an Ethernet hub or switch hub can to expand the network and Internet sharing to more than the four PCs directly supported by the router.
There are also single port routers on the market, routers that do not include an Ethernet switch or hub (http://duxcw.com/faq/network/hubsw.htm). I will review one shortly.
Another way to do it is with a software solution. There are two flavors: a proxy server and a NAT (Network Address Translator). I have found that a NAT works best for a small network. Windows 98 Second Edition (SE) and Millennium (Me) include ICS (Internet Connection Sharing; http://duxcw.com/digest/Howto/network/win98se/intro.htm and http://duxcw.com/digest/Howto/network/win98se_cab/intro.htm). It works OK for basic browsing and E-Mail functions, but has problems with some network games and conferencing programs, etc. It requires two network adapters in the PC connected to the Internet, one to the MODEM and the other to another PC via a crossover cable (http://duxcw.com/digest/Howto/network/cable/cable1.htm) or to a hub with a straight-thru cable as you have now. You would have to buy another adapter and cable.
Of the software I have tested, I have found that SyGate (http://duxcw.com/digest/Reviews/Network/sygate/sygate.htm) is the best NAT (it can also function as a proxy). The version of SyGate I reviewed requires two network adapters like Win 98 SE/Me ICS. The newest version is advertised to work with one network adapter in the host computer (the one running the NAT).
With a software solution you must have the host computer on for the other computer(s) (clients) to use the Internet. Most routers are small boxes running a specialized server that performs both NAT and firewall functions. With a router, only the router has to be on. The router is also easier to install, is generally faster, and has fewer problems.
Q. How can I set-up a computer with more than one network configuration so it can be conveniently used on multiple networks?
A. Check out Netselect (http://members.home.net/gbenton/software/NetSelect/). I have looked briefly at it, but have not had time to really try it out. If someone has experience with the software, please share your experience with a post to our Fourms
There are other ways to do it.

Q. What is the difference between an Ethernet hub and switch?

A. Although hubs and switches both glue the PCs in a network together, a switch is more expansive and generally considered faster than a hub. Why?
When a hub receives a packet (chunk) of data (a frame in Ethernet lingo) at one of its ports from a PC on the network, it transmits (repeats) the packet to all of its ports and, thus, to all of the other PCs on the network. If two or more PCs on the network try to send packets at the same time a collision is said to occur. When that happens all of the PCs have to go though a routine to resolve the conflict. The process is proscribed in the Ethernet Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol. Each Ethernet Adapter has both a receiver and a transmitter. If the adapters didn't have to listen with their receivers for collisions they would be able to send data at the same time they are receiving it (full duplex). Because they have to operate at half duplex (data flows one way at a time) and a hub retransmits data from one PC to all of the PCs, the maximum bandwidth is 100 Mhz and that bandwidth is shared by all of the PC's connected to the hub. The result is when a person using a computer on a hub downloads a large file or group of files from another computer the network becomes congested. In a 10 Mhz 10Base-T network the affect is to slow the network to nearly a crawl. The affect on a small, 100 Mhz, 5-port network is not as significant.
Two computers can be connected directly together in an Ethernet with a crossover cable (http://duxcw.com/digest/Howto/network/cable/cable1.htm).


A crossover cable doesn't have a collision problem. It hardwires the Ethernet transmitter on one computer to the receiver on the other. Most 100BASE-TX Ethernet Adapters can detect when listening for collisions is not required with a process know as auto-negotiation and will operate in a full duplex mode when it is permitted. The result is a crossover cable doesn't have delays caused by collisions, data can be sent in both directions simultaneously, the maximum available bandwidth is 200 Mhz, 100 Mhz each way, and there are no other PC's with which the bandwidth must be shared.
An Ethernet switch automatically divides the network into multiple segments, acts as a high-speed, selective bridge between the segments, and supports simultaneous connections of multiple pairs of computers which don't compete with other pairs of computers for network bandwidth. It accomplishes this by maintaining a table of each destination address and its port. When the switch receives a packet, it reads the destination address from the header information in the packet, establishes a temporary connection between the source and destination ports, sends the packet on its way, and then terminates the connection.
Picture a switch as making multiple temporary crossover cable connections between pairs of computers (the cables are actually straight-thru cables; the crossover function is done inside the switch). High-speed electronics in the switch automatically connect the end of one cable (source port) from a sending computer to the end of another cable (destination port) going to the receiving computer on a per packet basis. Multiple connections like this can occur simultaneously. It's as simple as that. And like a crossover cable between two PCs, PC's on an Ethernet switch do not share the transmission media, do not experience collisions or have to listen for them, can operate in a full-duplex mode, have bandwidth as high as 200 Mhz, 100 Mhz each way, and do not share this bandwidth with other PCs on the switch. In short, a switch is "more better."


4. RE: Notebook connected to Cable and DSL...?
Accessdabbler Aug-23-01 07:38 PM
In response to message 3
Yikes!

Read and understood (mostly).

Therefore, I need to put a router at both locations and set them up with the same gateway address (such as 192.168.0.100) for the router. The notebook will also need to have a static IP address (such as 192.168.0.99).

This, I presume, will eliminate the need to use WinGate?

Finally, can I "trust" the firewall capabilities of the router? I use ZoneAlarm Pro on my main server computer as added protection. Will I need to put ZoneAlarm on each computer now that the router is the "server"?


6. RE: Notebook connected to Cable and DSL...?
lbyard Aug-23-01 08:03 PM
In response to message 4
You could use DHCP and refresh the IP. A gateway setting is not needed.
This, I presume, will eliminate the need to use WinGate? Yes (and work much better and faster as well).

I'll take my Barricade router’s firewall over any software firewall solution any day. I think a PC running firewall software is much more vulnerable than a dedicated solution. Do you want an intruder to get as far as your LAN and PCs or stop “it” before it gets that far? A software firewall may also present configuration problems with routers.

Larry


8. RE: Notebook connected to Cable and DSL...?
lbyard Aug-23-01 08:12 PM
In response to message 4
The static IPs will dpend on how the router is setup. For example, mine would be 192.168.123.x for use with a Barricade with defaults set (and the DHCP server reconfigured not to interfer). Larry

9. RE: Notebook connected to Cable and DSL...?
Accessdabbler Aug-23-01 08:34 PM
In response to message 8
Only thing left to do now is try and make it work.......

Thanks!

Bruce.


| Home | Guides | How to | Reviews | Online Store | FAQ | Forums | Forum Archives |
| Links | News | Newsletter | About Dux | Advertising | Contact Info | Privacy |