Client Lease Time? LINKSYS Router

What's the ``client lease time''? You can set it to xxxx minutes, ``0 means one day''

It's in the section for starting and ending IP addresses that it should assign.
--


On the internet, nobody knows you're a jerk.

Hi!

> What's the ``client lease time''?

Client lease time refers to how long a computer will "lease" an IP
address and other TCP/IP configuration information from your router.
If you were to set it to, say, thirty minutes, your computer would ask
the router every thirty minutes for a new DHCP lease. The router would
then hand out a renewed lease to the computer for the same length of
time. Depending upon the router, the computer might also get a
different IP address.

If all the devices on your network have fixed IP addresses, the client
lease time setting will do nothing. It's only for devices that get
their IP address from the router using DHCP.

William

wrote:
>
> Hi!
>
> > What's the ``client lease time''?
>
> Client lease time refers to how long a computer will "lease" an IP
> address and other TCP/IP configuration information from your router.
> If you were to set it to, say, thirty minutes, your computer would ask
> the router every thirty minutes for a new DHCP lease. The router would
> then hand out a renewed lease to the computer for the same length of
> time. Depending upon the router, the computer might also get a
> different IP address.
>
> If all the devices on your network have fixed IP addresses, the client
> lease time setting will do nothing. It's only for devices that get
> their IP address from the router using DHCP.
>
> William

Hmm. So supposing I'm downloading a file that will take over a day (dialup),
what happens if my IP address changes, if the client lease time is set to
the default of one day?

Not sure I understand the implications, not that I have the problem given.
--


On the internet, nobody knows you're a jerk.

Hi!

> Hmm. So supposing I'm downloading a file that will take over a day
> (dialup), what happens if my IP address changes, if the client lease
> time is set to the default of one day?

As far as I can tell, router and PC will cope just fine. I pulled a 6GB ZIP
file and a 4.7GB Knoppix disc image down from the 'net some time ago. Even
on a cable connection it took several days and exceeded the lease time on my
router. There were no problems or interruptions.

Since you mentioned a dialup connection, I must ask...is your Linksys router
actually doing routing from a dial-up connection? I've only ever seen one
router that could do that--the Apple Airport.

William

William R. Walsh wrote:
>
> Hi!
>
> > Hmm. So supposing I'm downloading a file that will take over a day
> > (dialup), what happens if my IP address changes, if the client lease
> > time is set to the default of one day?
>
> As far as I can tell, router and PC will cope just fine. I pulled a 6GB ZIP
> file and a 4.7GB Knoppix disc image down from the 'net some time ago. Even
> on a cable connection it took several days and exceeded the lease time on my
> router. There were no problems or interruptions.
>
> Since you mentioned a dialup connection, I must ask...is your Linksys router
> actually doing routing from a dial-up connection? I've only ever seen one
> router that could do that--the Apple Airport.
>
> William

No, I'm actually dialup on the internal modem. I just needed an example.

One case where it might matter is if programs in 2 computers are communicating
by shared files, say I1200a reading files in //I1200b and vice versa; and if
it goes on more than a day, then the actual IP addresses might change, if the
lease time expires.

That would screw things up if the file handles are resolved once at start rather than
each time (which seems likely in fact); and then the communication path would
break when the lease expired.

I can't guess whether there's enough programming to reresolve an expired handle
or not, this being a matter of psychology.
--


On the internet, nobody knows you're a jerk.

> -----Original Message-----
> From: Ron Hardin [private.php?do=newpm&u=]
> Posted At: Tuesday, August 21, 2007 1:58 PM
> Posted To: alt.sys.pc-clone.dell
> Conversation: Client Lease Time? LINKSYS Router
> Subject: Re: Client Lease Time? LINKSYS Router
>
> William R. Walsh wrote:
> >
> > Hi!
> >
> > > Hmm. So supposing I'm downloading a file that will take over a
day
> > > (dialup), what happens if my IP address changes, if the client
> lease
> > > time is set to the default of one day?
> >
> > As far as I can tell, router and PC will cope just fine. I pulled a
> 6GB ZIP
> > file and a 4.7GB Knoppix disc image down from the 'net some time
ago.
> Even
> > on a cable connection it took several days and exceeded the lease
> time on my
> > router. There were no problems or interruptions.
> >
> > Since you mentioned a dialup connection, I must ask...is your
Linksys
> router
> > actually doing routing from a dial-up connection? I've only ever
seen
> one
> > router that could do that--the Apple Airport.
> >
> > William
>
> No, I'm actually dialup on the internal modem. I just needed an
> example.
>
> One case where it might matter is if programs in 2 computers are
> communicating
> by shared files, say I1200a reading files in //I1200b and vice versa;
> and if
> it goes on more than a day, then the actual IP addresses might change,
> if the
> lease time expires.
>
> That would screw things up if the file handles are resolved once at
> start rather than
> each time (which seems likely in fact); and then the communication
path
> would
> break when the lease expired.
>
> I can't guess whether there's enough programming to reresolve an
> expired handle
> or not, this being a matter of psychology.
> --
>
>
> On the internet, nobody knows you're a jerk.


I move upwards to 200GB a day between machines on my home LAN and have
never seen a problem. As I mentioned, the router will assign the same
IP. Honestly, I don't think it does anything if machines are not
competing for IP addresses.

Ron Hardin <> wrote in
news::

> William R. Walsh wrote:
>>
>> Hi!
>>
>> > Hmm. So supposing I'm downloading a file that will take over
>> > a day (dialup), what happens if my IP address changes, if the
>> > client lease time is set to the default of one day?
>>
>> As far as I can tell, router and PC will cope just fine. I
>> pulled a 6GB ZIP file and a 4.7GB Knoppix disc image down from
>> the 'net some time ago. Even on a cable connection it took
>> several days and exceeded the lease time on my router. There
>> were no problems or interruptions.
>>
>> Since you mentioned a dialup connection, I must ask...is your
>> Linksys router actually doing routing from a dial-up
>> connection? I've only ever seen one router that could do
>> that--the Apple Airport.
>>
>> William
>
> No, I'm actually dialup on the internal modem. I just needed an
> example.
>
> One case where it might matter is if programs in 2 computers are
> communicating by shared files, say I1200a reading files in
> //I1200b and vice versa; and if it goes on more than a day, then
> the actual IP addresses might change, if the lease time expires.
>

AIUI the DHCP client initiates renewal of its IP address lease 50%
of the way into the lease period, and repeats the request
periodically thereafter until it is resolved. The DHCP server
(should) grant renewal of an existing IP address lease if at all
possible, and the cycle repeats. Hence if everything is working as
expected, a DHCP client will retain its allocated address whilst
it is active on the network.

It's the amount of time for which "client PCs" connected to the router
"lease" the IP address that the router's DHCP server gives them. Don't
worry about it, it's a low-level detail that is totally irrelevant to
virtually all end users at your level.


Ron Hardin wrote:
> What's the ``client lease time''? You can set it to xxxx minutes, ``0 means one day''
>
> It's in the section for starting and ending IP addresses that it should assign.

Hi!

> I can't guess whether there's enough programming to reresolve an expired
> handle or not, this being a matter of psychology.

I would tend to say that there is. I do a monthly backup with my laptop to
another computer. Both have dynamically configured IPs and it works fine.

While my present router (a Buffalo model flashed with the DD-WRT firmware)
has a setting to store the IP address it handed out to a given MAC address
in NVRAM (so as to ensure that the same IP goes to the same network adapter
each time), I have done the same backup with routers that had no memory of
what they'd done earlier and send out a different IP each time. These
backups did run long enough to exceed the normal lease time.

If you were doing something mission critical that must succeed, I would
advise defining "hard-wired" IP addresses for each client on the network.
That way you can be assured that address changes won't cause problems.

William

It does not matter in any case. The lease is automatically renewed,
there is not loss of service .... none, not even for a microsecond.

The ONLY significance of the lease time is that if a lease expires while
the computer is OFF, then when the computer is turned back on, it MIGHT
get a different IP address than it had before. So a longer lease time
insures a longer period of time with a guaranteed "same IP address".
[If the computer is ON when the lease expires, it will be renewed with
the same IP address in every case that I am aware of.]


Ron Hardin wrote:
> William R. Walsh wrote:
>> Hi!
>>
>>> Hmm. So supposing I'm downloading a file that will take over a day
>>> (dialup), what happens if my IP address changes, if the client lease
>>> time is set to the default of one day?
>> As far as I can tell, router and PC will cope just fine. I pulled a 6GB ZIP
>> file and a 4.7GB Knoppix disc image down from the 'net some time ago. Even
>> on a cable connection it took several days and exceeded the lease time on my
>> router. There were no problems or interruptions.
>>
>> Since you mentioned a dialup connection, I must ask...is your Linksys router
>> actually doing routing from a dial-up connection? I've only ever seen one
>> router that could do that--the Apple Airport.
>>
>> William
>
> No, I'm actually dialup on the internal modem. I just needed an example.
>
> One case where it might matter is if programs in 2 computers are communicating
> by shared files, say I1200a reading files in //I1200b and vice versa; and if
> it goes on more than a day, then the actual IP addresses might change, if the
> lease time expires.
>
> That would screw things up if the file handles are resolved once at start rather than
> each time (which seems likely in fact); and then the communication path would
> break when the lease expired.
>
> I can't guess whether there's enough programming to reresolve an expired handle
> or not, this being a matter of psychology.