hayes@Apple.COM (Jim Hayes) (05/21/91)
Awhile back, I promised to tell you what we use/how we build our network. This is pretty much it as for as the Product Development side goes. I posted this originally in April '90. Now we've about doubled in size... (This new version has been updated considerably. :-) --- Apple's Engineering Network: (The network run by MIS is much different, don't get them confused.) We support three protocols (sometimes four, depending on who you ask) on our internal Product Development network spanning 53 local buildings and several foreign countries. They are AppleTalk, TCP/IP, Apollo Domain and maybe DECnet. We support AppleTalk Phase II and TCP/IP on all Ethernet and FDDI networks within product development. We support Apollo Domain on demand so it doesn't go everywhere. We may soon be supporting DECnet in a limited fashion, but that is still up in the air with a <5% probability. We don't bridge anything. There are two official Shiva FastPath boxes on our network that handle DDP/IP translation for LocalTalk users. There are a few renegade FastPaths on the network as well performing various engineering tasks. The network goes *everywhere* engineering goes, and appears at every desktop in the form of a 10MB/s connection (Thin Ethernet, UTP (pre 10baseT) Ethernet, or 10baseT.) and Localtalk. Depending on where you sit, you may get RGB video at your desk too, or the even the AppleTV cable system. Stats: (as of 5/20/91) 515 LocalTalk networks (mostly laserprinters and backup connections. If your coax breaks, just use LocalTalk for a few hours until it's fixed.) 98 EtherTalk networks (mostly users, 10MB/sec) 100 IP Networks (the same wires as the EtherTalk net + a couple transit networks) 225 AppleTalk Zones 326 Apple Internet Routers (most of the LocalTalk routing is done here. ) 31 IP/AppleTalk high-performance routers 5 IP only medium-performance routers 53 Buildings (not including foreign countries) >1500 File Servers (Artifact of System 7.0 filesharing.) 105 QuickMail servers (w/Internet & Applelink gateways) 3811 QuickMail users 968 Laser printers (excluding shared spoolers) 1 Cray Supercomputer with a direct 100MB link to the FDDI backbone. (XMP will be replaced with YMP-2E soon. >1 Terabyte (1000 Gigabytes) of online network accessible storage. >5000 users (conservative guess. The software that provides an accurate count isn't ready yet. :-) 23 Gigabytes routed per day is a typical load on some of our high-performance routers. Specs.: Packets travel to stub networks mostly by fiber optic cable at 10 MB/sec. The backbone is a 100MB/sec FDDI Ring. (Soon to be split into two separate FDDI rings with redundant routing between.) Remote sites out of reach from our fiber-hub connect with 45Mb/s T3, 1.5Mb/s T1 or 56Kb/s service. Transports may be encrypted microwave (T3), dark copper or telco-supplied copper (T1), and dark, switched, or telco copper for 56K. Various circumstances may require that we mux several 56K links onto fiber as a transport media to our facilities. The microwave system also supports a T1 channel and 2 broadcast quality composite video channels. A packet arrives at its destination in under 5 milliseconds on average, but it can be as fast as 1 ms. Packets from California to Paris arrive in 112ms, packets to the East coast arrive in under 60ms. Packets to Japan arrive in 313ms. The most distant end-to-end IP connection traverses 5 routers. The most distant end-to-end AppleTalk connection traverses 9 AppleTalk routers. Management: The network is maintained by 12 people (3 technicians, 7 analysts and a software engineer.) and 2 computers. Oh yeah-- there's the boss in there somewhere. One analyst or technician is on-call after-hours on a rotating basis. The computers monitor network integrity and automatically alert the appropriate people when failures occur via Motorola pagers. They gather and analyze statistics by drawing pretty graphs and perform trend analysis as well. This is accomplished by a Mac II and a Sun 3 (Soon to be a SPARC!) running custom and commercial software. One person in each workgroup is appointed a network liaison and is the first defense/resource used in solving user problems. The liaisons (known as FONTs, or Federation of Network Technologists) meet every so often to discuss networking issues and trade troubleshooting hints. If problems cannot be solved by the liaison, they come to the the analysts. Depending on the skill level of the FONT, they may have already restarted routers, used management tools or performed physical layer troubleshooting. Philosophy: Each office is wired for: LocalTalk, 10Mb/sec. Ethernet and RS-232 (RS-232 comes from the telephone set.) Users use what works best for them. Troubleshooting can occur down to the port in very short order. With SNMP support it's even faster. The network is not bridged anywhere. We believe strongly that a routed network is a reliable network. Firewalls are quite necessary, especially with the high number of third party systems sitting on the network. End-to-end connectivity: You can get to anywhere from anywhere on the network using AppleTalk *OR* TCP/IP. Security: No direct dial-in modems... Restricted access to/from the national Internet. Periodic network sweeps for unauthorized connections. Purchasing: Invest in quality, high performance network components. Avoid false economies in equipment, they are long term liabilities. Test and Evaluate EVERYTHING before it goes on the network. Stay on the bleeding edge of technology, and take calculated risks when necessary. Selected Hardware: (This is a list of the major vendors we use, and does not constitute an official endorsement for any particular vendor. Again, this is a partial list of the major vendors) Apple Computer Inc: Macintosh II{x,cx,ci,fx)'s running the AppleTalk Internet Router software. Apple EtherTalk NB ethernet cards. Cisco systems: Various high-performance router models, mostly AGS and AGS+ boxes, usually 8 to 12 ethernet ports and 1 FDDI port on each. Two 16 port terminal servers. X.25 Protocol Converter for various test/production systems. NetCentral Station monitoring software. Cabletron: Thick-Thin repeater, slowly being replaced by Twisted Pair stuff. MMAC 10BaseT concentrators (one) 10Base T Transceivers Fiber repeaters Tons of TMS-3 Tranceivers +Lots of RG58U coax & tranceiver cables. Canoga Perkins: 8803 Fiber Repeaters, fantastic performance. ???? Fiber Mux for multiple V.35 to fiber connections Digital Link: CSU/DSU's for T1 connections. FiberMux: V.35 to Fiber for multiple V.35 connections Microwave Networks, Inc.: T-3/T-1/Video Encrypted microwave gear Modunet: "Phone-Net" like LocalTalk "drop boxes" Network Systems: EN641 routers. (less than 5) IP Only 8 ports per box + FDDI connections. Retix: Local and Remote SNMP bridges Synoptics: Model 2500 Concentrators in closets (twisted pair) Model 2600 Twisted pair to thin-net converters. 3000 series chassis Telebit: TrailBlazer+, 1500, 1600, 2000, 2500 modems for secured connections. US Robotics: Courier HST modems. So, that's how we do it... Jim Hayes, Apple Computer, Inc. Inet: hayes@apple.com UUCP: {amdcad|decwrl|ames}!apple!hayes AppleLink: HAYES
roy@phri.nyu.edu (Roy Smith) (05/27/91)
hayes@Apple.COM (Jim Hayes) writes:
-> Transports may be encrypted microwave (T3), dark copper or telco-supplied
-> copper (T1), and dark, switched, or telco copper for 56K.
What's "dark copper"?
--
Roy Smith, Public Health Research Institute
455 First Avenue, New York, NY 10016
roy@alanine.phri.nyu.edu -OR- {att,cmcl2,rutgers,hombre}!phri!roy
"Arcane? Did you say arcane? It wouldn't be Unix if it wasn't arcane!"