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FTP setup problem

- no such thing as blocking FTP function - it's just more 1s and 0s through TCP.

Actually, that's not true. it's fairly easy to find the connection packets for FTP, because the protocol is quite verbose. There are boxes now that only do packet inspections as traffic goes through them, so they could easily silently drop FTP connection packets regardless of what port they're on.

A place I used to work for did this with P2P traffic, except instead of dropping the packets altogether, it modified one of the fields in the header so that it looked like there was a lot of network congestion and the speed was dropped to a 14.4 kbps modem.
 
Actually, that's not true. it's fairly easy to find the connection packets for FTP, because the protocol is quite verbose. There are boxes now that only do packet inspections as traffic goes through them, so they could easily silently drop FTP connection packets regardless of what port they're on.

this isn't identifying FTP ... just the steady stream of packets being uploaded from an IP - which could be from any of a number of system configurations. As you describe, one would see the setup work for a period and then drop once the packet inspections were identified. Personally, I don't think there is a great deal of money spent on seriously chasing FTP.
 
Yes, but all you have to do is make the connecting packets disappear ("lose" or drop them somewhere between the source and destination), and no connection can be made, so no data can be sent. Both computers have to know that there's a connection being made before anything can be transferred, so if you stop the connection in the first place, no transfers can take place.

Anyway, it's all theoretical, and we need the OP to try setting up an FTP server on his box and connect it directly to the Internet to see if Telus is blocking FTP connections, or whether there's something misconfigured at the router level.
 
xentr_thread_starter
IP parameters

Can anyone clarify for me the relationship between router (Linksys WRT54GL) IP parameters and those of the FTP server (Nexstar LX)? The router's Subnet Mask, Gateway, Primary DNS and Secondary DNS were provided by my ISP. How do the settings on the LX relate to these? What should they be?

Currently, my router shows the following:
IP address: ppp.ppp.ppp.ppp
Subnet mask: 255.255.224.0
Default gateway: ***.***.***.***
Primary DNS: yyy.yyy.yyy.yyy
Secondary DNS:zzz.zzz.zzz.zzz

The FTP server has:
IP address: 192.168.1.10
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Primary DNS: yyy.yyy.yyy.yyy (same as router)
Secondary DNS:zzz.zzz.zzz.zzz (same as router)

Thanks for your help.
 
looks good to me

Can anyone clarify for me the relationship between router (Linksys WRT54GL) IP parameters and those of the FTP server (Nexstar LX)? The router's Subnet Mask, Gateway, Primary DNS and Secondary DNS were provided by my ISP. How do the settings on the LX relate to these? What should they be?

Currently, my router shows the following:
IP address: ppp.ppp.ppp.ppp
Subnet mask: 255.255.224.0
Default gateway: ***.***.***.***
Primary DNS: yyy.yyy.yyy.yyy
Secondary DNS:zzz.zzz.zzz.zzz

The FTP server has:
IP address: 192.168.1.10
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Primary DNS: yyy.yyy.yyy.yyy (same as router)
Secondary DNS:zzz.zzz.zzz.zzz (same as router)

Thanks for your help.

This all looks ok to me. The Nexstar LX is obtaining it's IP configuration from the Linksys router if you are using default configurations for both the Linksys and Nexstar. When the Nexstar is booting up it makes a request for IP parameters from a DHCP server. The Linksys is responding that it is the DHCP server and provides the IP info to the Nexstar.
 
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Code:
Router:
IP address: ppp.ppp.ppp.ppp
Subnet mask: 255.255.224.0
Default gateway: ***.***.***.***
Primary DNS: yyy.yyy.yyy.yyy
Secondary DNS:zzz.zzz.zzz.zzz

FTP Server
IP address: 192.168.1.10
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Primary DNS: yyy.yyy.yyy.yyy (same as router)
Secondary DNS:zzz.zzz.zzz.zzz (same as router)

why are your subnets differnet?
 
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xentr_thread_starter
why are your subnets differnet?

I have no idea. Should they be the same? Which one is correct? As I have access to the web I assume that the router subnet entry of 255.255.224.0 is correct.

I've just found a piece of advice elsewhere on the web saying that the Primary DNS should read 192.168.1.1, the same as the Gateway. No success with that change either.
 
I have no idea. Should they be the same? Which one is correct? As I have access to the web I assume that the router subnet entry of 255.255.224.0 is correct.

I've just found a piece of advice elsewhere on the web saying that the Primary DNS should read 192.168.1.1, the same as the Gateway. No success with that change either.

Give me the exact info off of the router AND the server

IP, Gateway, Subnet.

DNS only needs to be specified if you have setup your router as static IPs and the DNS needs to be that for your ISP.
 
different networks may have different Subnet Masks

Code:
Router:
IP address: ppp.ppp.ppp.ppp
Subnet mask: 255.255.224.0

FTP Server
IP address: 192.168.1.10
Subnet mask: 255.255.255.0
why are your subnets differnet?

Because the networks are different. The ISP has many networks of which the OP is one of and the LAN has one.

Subnetwork - Wikipedia, the free encyclopedia
 
Because the networks are different. The ISP has many networks of which the OP is one of and the LAN has one.

Subnetwork - Wikipedia, the free encyclopedia

The users network is absolutely no different than anyone elses.

He has high speed internet, their modem, a router and a ftp server.

The router gets the ip from the isp and the computer and ftp server gets it from the router so that means the computer subnet and the ftp server subnet should be the same.

He is going to have to setup his router to assign static ips then manually setup the rest of the network UNLESS the ftp server will only run using DHCP.
 

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