You're correct that all USB 2.0 conformant hubs,
including the root hub that is part of a host (even if it has only one USB port) must support high speed.
Anyhow, what consumers should look for is not a "USB 2.0" label, but rather the "USB High Speed" logo, since USB 2.0 devices (as opposed to hubs) may not support high speed.
Any product that fully complies with the USB2.0 specification is capable of running at 480mbps.
Sorry, but you're mistaken. Perhaps you should actually read the USB 2.0 specification. But in the mean time, I quote from page 119:
The USB 2.0 specification requires hubs to support high-speed mode. USB 2.0 devices are not required to
support high-speed mode.
In plain language, a USB 2.0 hub or host (root hub) must support 480 Mbps operation, but a USB 2.0 device need not. In fact, a USB 2.0 device doesn't even have to support 12 Mbps operation. It is perfectly acceptable to have a low-speed only USB 2.0 device, though such a device is required to have a captive cable.
Generally low-speed only USB devices are HID class devices such as keyboards and mice, though this is not required.
No, it's not. The USB 2.0 standard included the 1.5 Mbps, 12 Mbps, and 480 Mbps modes from day one. This isn't something new. It's been entirely possible all along to have fully compliant USB 2.0 devices that don't support 480 Mbps.
To label a product as USB2 when it's really USB1.1 and conforming to the IEEE specifications for USB1.1 is fraudulent.
What if the product fully complies to the USB 2.0 specifications? Which it may be able to do even though it was originally only designed with the USB 1.1 specifications in mind? If it meets the USB 2.0 specifications, which do not require support of the 480 Mbps data rate, calling it a USB 2.0 device is at least technically correct, and not fraudulent as you claim.
However, I'll agree that it's rather sneaky and underhanded to simply market a 12 Mbps USB 2.0 device as "USB 2.0" without any explanation of
the supported data rates.
By the way, there is no IEEE specification for USB. Therefore there are no products that conform to "the IEEE specifications for USB 1.1". It's a standard of the USB Implementer's Forum.
Didn't the 9/11 attacks on the trade center use planes departing from NYC headed to San Fransisco? Or... that's it, domestic flights!
Yes, those were domestic flights. And the hijackers either were not listed on the "no-fly" list, or had fake IDs, or the list wasn't checked properly. Thus the "no-fly" list is ineffective, unnecessary, and serves no useful purpose. It merely costs taxpayers and/or airline customers money, and causes legitimate travellers to be harassed.
The US government has a legitimate interest in knowing what foreign nationals enter and leave the US, and has the proper constitutional authority to control that. They have neither a legitimate interest nor constitutional authority to control travel between states, to demand identification of domestic travellers, or to have a blacklist for doemstic travellers.
How would not allowing US passport holders onto aircraft have prevented any of the incidents you cite?
By your reasoning, why should they allow people into an automobile without checking them against a "no drive" list? Why should they allow people into a public library without checking them against a "no read" list? Why shouldn't they just tattoo a list of what actions you're allow to perform on your forehead?
How does government come up with a strategy that allows us to fight terrorism ferociously without gutting our civil liberties?
There's a simple, easy, inexpensive and effective solution. Unfortunately that's not what the government wants; they prefer expensive, complicated solutions that let them hire more people and expand the bureacracy, even if it happens that those solutions are ineffective. Anyhow, the simple, easy, inexpensive solution is:
On domestic flights, don't use a don't fly
list at all. It's completely unnecessary
and serves no useful purpose.
On international flights, if it's absolutely
necessary (and I'm not convinced that it is), use such a list
only for passengers that aren't carrying a valid US passport.
like cellular phone headsets. It's not intended
to be the all-singing all-dancing wireless solution
for everything. If you try to use it for purposes
for which it is not well-suited, of course it's not
going to be great.
A friend has a riding lawnmower. It's a great vehicle when used to mow the lawn. If you tried to
use it for a trip to the grocery store, it would
completely suck.
I too have the T68i and Jabra. I loved it at first. The battery actually lasted for more than the rated three hours of talk time, and the range was more than ten feet. But a month later, I find that the battery life is now less than an hour of talk time, and the range has dropped to under three feet. Maybe the non-user-replacable battery in the headset has gone bad or something. I'm going to call Jabra about it this week.
I'm not sure whether it's due to a bug in the T68i phone, or in the headset, but I find that trying to train the phone's voice dialing using the headset (which is what Jabra recommends) only rarely works, and often the phone crashes during the attempt and I have to remove the battery. I ended up training the voice dialing without using the headset, and it seems to work fine. I suspect it's a bug in the phone, because there shouldn't be anything an external device can do to crash the phone. Even if a Bluetooth device mangled the protocol in horrible ways, the phone still shouldn't crash. And I've certainly found other bugs in the phone, though I mostly like it.
A friend told me that there was a firmware upgrade for the headset (also not user-installable), and that Jabra offers an advanced exchange if you give them a credit card number. I haven't confirmed this.
And how many companies that don't already have an investment in token ring do you think are buying new token ring gear now? Answer: none at all.
Token ring had some minor technical advantages over 10base5 and 10base2 ethernet years ago, but also had some substantial disadvantages. The introduction of 10baseT hubs mostly negated token ring's advantages, and the introduction of Ethernet switches have put Ethernet unquestionably far ahead of token ring. There is now literally no technical basis for choosing token ring for a new network.
In the early to mid 1990s, I was a software developer writing software for multiprotocol routers. We supported token ring, but we had very few customers for it even then. Today I seriously doubt that we'd be able to sell any, even to banks and airlines.
The banks around here might still have some token ring equipment in operation, but all their new stuff seems to be 100baseT and 1000baseT.
I think you mean that they gave you a/80, so that you have 48 bits
of address under your control. Or perhaps I have the terminology wrong.
Anyhow, the reason for giving you 48 bits is that your Ethernet devices (and any other 802 networking
devices) can simply use their MAC address as the last 48 bits of their
IPv6 address, thus avoiding the need for manual assignment or for a
DHCP-like dynamic address allocation scheme.
It will certainly be nice if that proves to be standard practice.
There was a nice overview of the IPv6 protocol in an article in one of
the Linux magazines recently, possibly the January 2003 issue of Linux
Journal but I'm not sure. Anyhow, the article dicussed the various types
of IPv6 address assignment, but I don't recall the details.
The reason for having 128-bit adresses isn't that we can expect to have 2^128 IP-enabled devices any time soon. (Unless there's a breakthrough in nanotechnology!) The reason is that it is in general not possible to assign the addresses efficiently.
In order to keep the routing tables for the backbones reasonable (only millions of entries, not billions), the addresses have to be doled out in a hierarchical fashion. At each level of the hierarchy some inefficency of allocation occurs.
The good news is that with IPv6, there won't be
any technical reason for your ISP to limit you to a miniscule number of IP addresses. They may still do it for marketing or product differentiation reasons. They really like the ability to charge per IP address. Because of this, I expect that NAT will be used even with IPv6, despite there being no technical need for it.
Others will switch to pre-existing, non-IP based, protocals with cheap interfaces like token ring(Think Novell and IPX).
Surely you jest. No one in their right mind would switch from IP to non-IP protocols at this point, and even if they did, they certainly wouldn't need to switch to Token Ring to do it. Token Ring is dead, dead, dead! And good riddance!
In theory you can never run out of IP addresses, as subnetting and further subnetting still will help alleviate the problem.
Huh? Even if you start from a/8 address (the largest IPv4 blocks ever assigned), you can only subnet a maximum of eight levels deep. Subnetting
does not create more usable addresses; it actually
uses up some addresses as overhead.
but Joe Average wouldn't know how to [run his own SMTP server]
Joe Average doesn't NEED to run an SMTP server. He just points his MUA at his ISP's SMTP server. Most ISPs now are set up to accept SMTP mail from their customers from any IP address (not just the customer's "home" IP address) provided that the connection is authenticated in one of several ways, commonly including logging in via POP or IMAP.
If your ISP does NOT allow you to send mail through their SMTP server from arbitrary IP address (subject to authentication), it's time to find a new ISP.
Checking the MX record of the domain in question would just be an extra step.
If you actually read the internet draft in question, you would realize that checking the RMX record (not MX) is an extra step that could be much more effective than the sorts of checks that are done today.
The reason it works better than existing checks is that it doesn't just verify that the sender's claimed domain exists (has an SOA or maybe MX record), but also if the new RMX record exists, it can verify that the IP address of the initiator of the SMTP connection is authorized to transfer email on behalf of that domain.
This is a great idea, because it can be phased in gradually. Owners of domain names that are commonly used fraudulently (e.g., hotmail.com) can add the RMX and APL records to their DNS, and then any MTAs that use RMX verification can determine whether the machine sending the mail is authorized. MTAs that don't use RMX are unaffected and will still receive mail regardless of RMX records. If a domain doesn't have an RMX record, a spammer can still forge mail from that domain, because even an RMX-enabled MTA will accept mail from that domain (though if RMX catches on, someday that may change).
If new versions of MTAs have RMX enabled by default, eventually more and more domain owners will respond to complaints about spam forged from their address by adding RMX records to their DNS.
Let's hope that sendmail, qmail, postfix, exchange, etc. implement this soon!
Apples-to-oranges comparison
on
802.11g Slows Down
·
· Score: 4, Informative
The numbers quoted in the article aren't measuring the same thing. 802.11g has a raw data rate of 54 Mbps, but it was never the case that you could get 54 Mbps throughput. Typical products got 20-22 Mbps throughput. Just as typical 802.11b products get around 5 Mbps throughput from an 11 Mbps raw data rate.
So if they made some change to the final 802.11g standard such that the througput is only 20 Mbps, that's not much of a change from the draft.
And it has always been the case that in a mixed enviornment (802.11b coexisting with 802.11g), you can't get maximum 802.11g throughput. The exact amount of slowdown will vary.
So in summary, I'm not convinced that anything this Computerworld article is reporting about the 802.11g standard is actually a significant change from the draft. They've just compared some numbers in a meaningless way to sensationalize the story.
Disclaimer: At work I'm involved in the development of 802.11g products.
"But there's a case where an accused kidnapper who was using a cloned cell phone sued for the interception of the cell phone conversations... And he won."
That's only because there's a federal law banning interception of cell phone conversations. That has absolutely nothing to do with honeypots, unless the honeypot someone intercepts cell phone conversations.
AFAIK, there isn't any federal law that says that the owner of foo.com can't set up a "fake" foo.com, or that he incurs any liability (financial or legal) for doing so. If J.R.Hacker has no authorization to access foo.com, then he has exactly the same level of authorization to access the fake foo.com, and has no legal grounds to complain that the fake system didn't actually contain the credit card numbers he was looking for.
The key is a Dallas Semiconductor I-button. It
contains 16 bytes of data, of which 11 bytes are
apparently a unique ID. It's possible to copy
keys, but if you have a Segway and no key, you'd
have to disassemble the Segway to extract its
ID.
If the makers were really clever, it may not be
possible to make a matching key even if you tear
apart the Segway. They may have designed it using
a non-invertable cryptographic hash such that the
code in the Segway can be derived from the code in the key, but not vice versa. In that case the
only way to do it would be to rekey the Segway, but they could have made that very difficult.
See Hacking Segway Keys for more information. That's mostly about modifying a key to change the performance characteristics (increasing the speed limit), but it talks about the key code as well.
I don't understand why so many seem opposed to such a change. Maybe some people imagine something similar to the old CD caddies, where you had to place the regular format in a cartridge.
People didn't like the caddies because they didn't
use them correctly. The idea was that when you
bought a CD-ROM, you put it in a caddy, and it
stayed there as long as you kept that disc. I
was always quite happy with the caddies using
Toshiba and Plextor CD-ROM and CD-R drives, and
was really unhappy when they stopped making
drives that used caddies.
production disks circa 1983-4 were still 5-20MB in a cabinet the size of a small desk, and 20 times heavier.
False. By 1981, there were 5 MB 5.25-inch "full-height" winchester drives from Shugart Technologies (which became Seagate Technology to avoid confusion with Shugart's earlier company) and a few
other vendors. By 1982 these were fairly common, and there were also 10 MB drives in that form factor.
Common rack-mount non-removable media drives were about 380 MB in a 19"x10.5"x30" package weighing about 130 pounds.
Common removable disk pack drives were about 200 MB, and were only half the size of a desk.
Any company that in 1983 was selling a 5-20 MB disk in a cabinet the size of a small desk was seriously behind the times.
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Anyhow, what consumers should look for is not a "USB 2.0" label, but rather the "USB High Speed" logo, since USB 2.0 devices (as opposed to hubs) may not support high speed.
However, I'll agree that it's rather sneaky and underhanded to simply market a 12 Mbps USB 2.0 device as "USB 2.0" without any explanation of the supported data rates.
By the way, there is no IEEE specification for USB. Therefore there are no products that conform to "the IEEE specifications for USB 1.1". It's a standard of the USB Implementer's Forum.
The US government has a legitimate interest in knowing what foreign nationals enter and leave the US, and has the proper constitutional authority to control that. They have neither a legitimate interest nor constitutional authority to control travel between states, to demand identification of domestic travellers, or to have a blacklist for doemstic travellers.
By your reasoning, why should they allow people into an automobile without checking them against a "no drive" list? Why should they allow people into a public library without checking them against a "no read" list? Why shouldn't they just tattoo a list of what actions you're allow to perform on your forehead?
There's a simple, easy, inexpensive and effective solution. Unfortunately that's not what the government wants; they prefer expensive, complicated solutions that let them hire more people and expand the bureacracy, even if it happens that those solutions are ineffective. Anyhow, the simple, easy, inexpensive solution is:
A friend has a riding lawnmower. It's a great vehicle when used to mow the lawn. If you tried to use it for a trip to the grocery store, it would completely suck.
I'm not sure whether it's due to a bug in the T68i phone, or in the headset, but I find that trying to train the phone's voice dialing using the headset (which is what Jabra recommends) only rarely works, and often the phone crashes during the attempt and I have to remove the battery. I ended up training the voice dialing without using the headset, and it seems to work fine. I suspect it's a bug in the phone, because there shouldn't be anything an external device can do to crash the phone. Even if a Bluetooth device mangled the protocol in horrible ways, the phone still shouldn't crash. And I've certainly found other bugs in the phone, though I mostly like it.
A friend told me that there was a firmware upgrade for the headset (also not user-installable), and that Jabra offers an advanced exchange if you give them a credit card number. I haven't confirmed this.
Token ring had some minor technical advantages over 10base5 and 10base2 ethernet years ago, but also had some substantial disadvantages. The introduction of 10baseT hubs mostly negated token ring's advantages, and the introduction of Ethernet switches have put Ethernet unquestionably far ahead of token ring. There is now literally no technical basis for choosing token ring for a new network.
In the early to mid 1990s, I was a software developer writing software for multiprotocol routers. We supported token ring, but we had very few customers for it even then. Today I seriously doubt that we'd be able to sell any, even to banks and airlines.
The banks around here might still have some token ring equipment in operation, but all their new stuff seems to be 100baseT and 1000baseT.
It will certainly be nice if that proves to be standard practice.
There was a nice overview of the IPv6 protocol in an article in one of the Linux magazines recently, possibly the January 2003 issue of Linux Journal but I'm not sure. Anyhow, the article dicussed the various types of IPv6 address assignment, but I don't recall the details.
In order to keep the routing tables for the backbones reasonable (only millions of entries, not billions), the addresses have to be doled out in a hierarchical fashion. At each level of the hierarchy some inefficency of allocation occurs.
The good news is that with IPv6, there won't be any technical reason for your ISP to limit you to a miniscule number of IP addresses. They may still do it for marketing or product differentiation reasons. They really like the ability to charge per IP address. Because of this, I expect that NAT will be used even with IPv6, despite there being no technical need for it.
Maybe you were thinking of NAT?
If your ISP does NOT allow you to send mail through their SMTP server from arbitrary IP address (subject to authentication), it's time to find a new ISP.
The reason it works better than existing checks is that it doesn't just verify that the sender's claimed domain exists (has an SOA or maybe MX record), but also if the new RMX record exists, it can verify that the IP address of the initiator of the SMTP connection is authorized to transfer email on behalf of that domain.
This is a great idea, because it can be phased in gradually. Owners of domain names that are commonly used fraudulently (e.g., hotmail.com) can add the RMX and APL records to their DNS, and then any MTAs that use RMX verification can determine whether the machine sending the mail is authorized. MTAs that don't use RMX are unaffected and will still receive mail regardless of RMX records. If a domain doesn't have an RMX record, a spammer can still forge mail from that domain, because even an RMX-enabled MTA will accept mail from that domain (though if RMX catches on, someday that may change).
If new versions of MTAs have RMX enabled by default, eventually more and more domain owners will respond to complaints about spam forged from their address by adding RMX records to their DNS.
Let's hope that sendmail, qmail, postfix, exchange, etc. implement this soon!
So if they made some change to the final 802.11g standard such that the througput is only 20 Mbps, that's not much of a change from the draft.
And it has always been the case that in a mixed enviornment (802.11b coexisting with 802.11g), you can't get maximum 802.11g throughput. The exact amount of slowdown will vary.
So in summary, I'm not convinced that anything this Computerworld article is reporting about the 802.11g standard is actually a significant change from the draft. They've just compared some numbers in a meaningless way to sensationalize the story.
Disclaimer: At work I'm involved in the development of 802.11g products.
AFAIK, there isn't any federal law that says that the owner of foo.com can't set up a "fake" foo.com, or that he incurs any liability (financial or legal) for doing so. If J.R.Hacker has no authorization to access foo.com, then he has exactly the same level of authorization to access the fake foo.com, and has no legal grounds to complain that the fake system didn't actually contain the credit card numbers he was looking for.
If the makers were really clever, it may not be possible to make a matching key even if you tear apart the Segway. They may have designed it using a non-invertable cryptographic hash such that the code in the Segway can be derived from the code in the key, but not vice versa. In that case the only way to do it would be to rekey the Segway, but they could have made that very difficult.
See Hacking Segway Keys for more information. That's mostly about modifying a key to change the performance characteristics (increasing the speed limit), but it talks about the key code as well.
Common rack-mount non-removable media drives were about 380 MB in a 19"x10.5"x30" package weighing about 130 pounds.
Common removable disk pack drives were about 200 MB, and were only half the size of a desk.
Any company that in 1983 was selling a 5-20 MB disk in a cabinet the size of a small desk was seriously behind the times.