Home
Class on DCC
Hello and welcome to our class on DCC.
Since this class is long, and you may want to review
what was said later, Please issue the following command
(in most IRC clients) to start logging the data sent to
the channel,
Please type this now:
/log on
I will start the class with a brief description of
what DCC is, and some of the dangers associated
with using it.
We will then go over the commands associated with DCC
both in general, and ones specific to this network.
Next, we will give some places to look if your having
problems connecting with another user using the DCC protocol
Finally, we will open the channel to a question and answer
session.
Before I go on with this class, I must give credit, where
credit is due. Much of the text in this class is directly
out of the /help function in mIRC. Thanks to the authors
of this very good tool.
DCC stands for "Direct Client to Client"
It is one of the protocols (rules for communication)
suppoted under IRC. When you use DCC you establish a
Direct link between your machine, and the other user of IRC
you are communicating with (bypassing the IRC servers).
DCC allows you to connect directly to another IRC client,
instead of going through the IRC Network,
to Send and Get files, and to Chat privately over a more
secure connection.
We will start this section with a list of the DCC related
commands. Then go into detail on each of them.
Standard DCC Commands:
/dcc chat
/dcc get
/dcc ignore
/dcc nick
/dcc reject
/dcc send
/dcc trust
/dccserver
DALnet specific Commands:
/dccallow
----
The /dcc chat command:
The /dcc chat nickname
This command is a way of initiating a dcc chat, where
nickname is the user with whom you want to dcc chat.
Notes: During this class:
The term 'nickname' should be replaced with the nick you wish
to communicate with.
the /dcc get command:
Command format: /dcc get folder
You can manually redirect an incoming dcc send
to a specific folder with the above command.
This will change the default folder mIRC uses as
the place it stores incomming data from a send by
another user (or fileserver).
note: this is a rarely used command and is an
alternate to using:
alt+o | dcc | folders
( Where alt + o means hold down alt key and press o )
and changing the information there.
the /dcc ignore command:
Accepting or Ignoring files:
This function is used in conjunction with the
setting in DCC Options section of mIRC.
It allows you to accept or ignore automatically
certain filetypes when someone tries to send you a file.
command format: /dcc ignore [on | off | accept | ignore]
/dcc ignore on (turn on auto ignore of filetypes)
/dcc ignore off (turn off auto ignore of filetypes)
/dcc ignore accept (turn off for short period) (note1)
/dcc ignore ignore (turn on for short period) (note1)
(note1): the time period is set in dcc options section of mirc.
WARNING - setting this to anything but ON can leave you open
to receiving virus data!
The /dcc nick command:
This option determines how mIRC behaves if someone changes
nicks during a send, get, or fileserver request.
By default, mIRC will pop up a dialog asking you if you
would like to accept the request in question. However you
can make mIRC automatically accept the request, or just
ignore all incoming requests.
Command format is: /dcc nick -sgcf oldnick newnick
and allows you to change the nickname associated with a
current dcc send/get/chat/fserve request.
The /dcc reject command:
You can manually redirect an incoming dcc send to a specific
folder with /dcc reject
You can use /dcc reject to reject the dcc send.
Note: Both of these commands must be called from within the
CTCP event or the on DCCSERVER send event.
(translation: This function is for use by
acomplished mIRC scripters only <wink>)
The /dcc send command:
The /dcc send command can also be used to initiate
a DCC Send to the specified nickname.
The format of the command is:
/dcc send -cl <nick> file1 file2 fileN
If you specify more than one filename, multiple dcc send
sessions to the specified user are initiated.
If you specify a wildcard filename, then the DCC Send
dialog will display files matching the wildcard.
The -c switch makes the dcc window close automatically
once the transfer has finished.
The -l switch limits the transfer rate to the max cps
limit specified in the 'DCC Fileserver'.
Note: If you want to connect to someone else's DCC Server
you can specify an IP Address and port instead of the
nickname, eg. /dcc send ipaddress:port
The /dcc trust command:
Trusted Users:
This allows you to add a list of trusted nicknames,
addresses, or user levels, from which mIRC will
automatically accept dcc sends.
You can use the format:
/dcc trust -r on | off | nick | address | level
pick either on or off to turn a users trust on or off
Specify either nick or address or level with the command
(but only one of the above) in the command to
change the trust list.
The /dccserver command:
DCC Server
The mIRC DCC Server listens for direct connections to your
IP address from other mIRC clients.
You can change the settings of the DCC Server from
the command line using:
/dccserver +/-scf on | off port
Since this command can make mIRC automatically accept DCC
requests, it should be used with extreme care.
The mIRC FileServer:
There is one other DCC related funtion in mIRC..
This is the FileServer funtion.
The mIRC fileserver allows other users to access
files on your hard disk and is therefore dangerous.
If used improperly, it will allow them to
access private/confidential information.
Due to the above, We will NOT be teaching anything
about how to setup or use the mIRC built in fileServer
in this (or any other) class.
Network specific command(s):
/dccallow command:
In an attempt to further protect users of
DCC functions. Many IRC networks (what mIRC talks to)
have added this command to restict who can send a user
files. It is not unlike the /dcc trust command built
into mIRC, but works at the server level of protcols.
Most IRC Networks that have implemented this command have
inplemented a help function. It can be accessed via:
/dccallow help
(output of the command is displayed in the 'status box)
use is as follows:
/dccallow +nickname (to allow user to send to you)
/dccallow -nickname (to NOT allow user to send to you)
note: Since this is a server level comand, once you leave
a network, the settings are dropped, and you must again do
an allow for trusted users the next time you come on the
network.
Problems connecting with another user using DCC
This section will only touch on the resolution of DCC
connect issues. It will however, point out the areas
that are the 'normal' things (that can be resolved with
a little work). It will point you to URL's that contain
details on how to resolve issues associated with PROXYs,
Firewalls, and also mIRC setup associated with DCC that
could cause problems (with proxy's and firewalls).
The #mIRC channel on most networks is a place users can
go to ask for help with DCC connection issues. However,
the URLs listed in this part of the class should be your
first point of reference (you may want to log this section
of the class if you are not doing so already (7/log on).
Thing we will cover related to DCC problems
Some basics and an overview
IP address: and how it relates to DCC functions
Firewalls: protect... (and get in the way)
Routers: How many computers do you have anyway!
BNC's: You BNC? DCC protocol Doesn't
(you can't have your cake and eat it too!)
Proxy Servers: What a mess they can make of DCC
Things outside your control: Why you can't DCC at School/Work
Most Basic check:
Is your problem with both sending and recieving,
or only with sends?
The ability to recieve, but not send can be caused
by several things, while both being blocked tend to
be caused by ip mismatch or scripts.
Checking for an ip mismatch is easy.
type: /dns yournickname
type: //echo -a $ip7
The two numbers, the one you see when you
type //echo -a $ip, and the other from the
number portion of what you get from typing
/dns yournickname must be the same.
If they arent, type: /localinfo -u
Then check again.
If they are still wrong you may need to disconnect
and in File / Options / Connect / LocalInfo,
clear the local host and ip address boxes.
Check on connect always get local host, and
try using server as the look up method instead
of normal.
IP Address:
Your IP address is your adress on the internet. It is set,
when you connect to the internet, by the Internet Service
Provider (ISP) you connect to.
This information will normally be filled in by mIRC and is
here mainly for your information.
mIRC looks up your IP address and stores it in the mirc.ini
file for future reference.
This way it doesn't have to look it up every time you want
to connect (via DCC).
If mIRC is having trouble getting your IP address
(when you first start mIRC) then you can enter this
value manually and mIRC will assume that it is correct.
If this value is wrong you will still be able to log on to
IRC but you will not be able to initiate DCC Send/Chat
sessions (you will only be able to accept them).
Your Local Host and IP Address are needed if you want to use
the DCC capabilities of mIRC.
for more information on IP Address, in mICR, you can type:
/help ip address
Firewalls:
Firewalls are a very good thing, they give you a great deal of
protection from people who want to do you wrong while on IRC.
However, if they are not configured correctly, DCC functions
will not work.
The concept of how a firewall works is simple... it monitors
your incomming data, you define to it: which ports, addresses,
etc. you wish to allow to get through to you.
So, DCC communications have to be within the range of your
accepted parmameters (for firewall and IRC client), or they
will not get through.
This does NOT mean you can not DCC with a firewall, but it
does mean you will need to configure both mIRC
(or any other IRC client software), and your firewall,
so they can work with DCC.
It also means that the person you establish DCC communicating
with, must also follow the rules you have setup in your
firewall (and irc client).
The configuration of individual firewalls, and mIRC is to
involved a subject to cover in this class. However, the
following link (url address) will help you in this area.
http://www.mirc.org/dcchelp.html
routers:
A router is a hardware and software combination that lets
multiple computers share the same internet connection
(IP address to the internet). It does this by presenting to
the internet multiple psudo addresses for each machine
behind the router. Since these are psudo addresses, the
router must know how to pass data to the individual machine
it was ented to go to (machines on your 'local network')
It is possible to configure mIRC and a router so that
machines behind the router (the local net machines) can
use DCC.
Since the particulars of how to do this are unique to each
of many kinds of routers, we will not address this in the
class but will, rather, privide you with a list of URLs that
will help you with this task (based upon type of router).
While this list is not a complte one, it will cover most of
the most common routers. Here it is:
http://www.mirc.org/dccprob.html
BNC's:
A BNC (sometimes called a bouncer) is a server which lets you
'pass through' to an IRC server. In the process it masks your
true IP address and (in some cases) gives you a fake 'mask'.
Since DCC Protocol depends on accurate IP address information,
DCC functions do not work when you use a BNC. End of story.
Translation: If you want to DCC get/send/chat, do not use a BNC.
Proxy Servers:
Things outside your control:
If you are at school, or at a place of business, you are
almost always on a local area net. Since you do not have
access (or authority) to modify the router in this
environment you normally can not use DCC.
This is done to protect the assets of the school or
business. (And why are you on IRC when you should be
working or hitting the books, anyway <wink>)
URL's for more information on DCC issues:
Here is a fairly comperhensive list of URLs that can
address DCC issues as related to IRC. We hope they
resolve your problems. However, if they do not, please
remember that the operators in #mIRC channel on most
networks can (and will) help you.
basic DCC help:
http://www.mirc.org/dcchelp.html
In depth DCC help:
http://www.mirc.org/dccprob.html
Windows XP Specific:
http://www.mirc.org/xphelp.html
'Wingate' a commonly used windows proxy server:
http://www.deerfield.com/wingate/
Some helpful tips and sample configurations for
using mIRC with ICS, Wingate, and Firewalls:
http://www.borg.com/~chuck/using.htm
Help with Linksys routers (for mIRC client):
http://www.practicallynetworked.com/support/linksys_router_help_pg4.htm#mIRC
13mIRC.com's proxy help:
href="http://www.mirc.co.uk/help/proxies.html
DALnet's proxy help:
http://kline.dal.net/proxy/index.html
TCP/IP books and resources:
http://www.landfield.com/faqs/internet/tcp-ip/resource-list
http://www.books.mfi.com/lan/LANTut3rdEd.html
http://www.wizard.com/users/baker/public_html/NetTutor.html
Information on Send Problems:
http://www.mirc.co.uk/help/sendproblems.html
Conceal Firewall:
http://www.conceal8.com
ZoneAlarm Firewall:
http://www.zonealarm.com
13Info on Cable modems:
http://www.cablemodeminfo.com/cmbasicsx.html-ssi
Help with Cable modems:
http://www.cablemodemhelp.com/
Help with DSL modems
http://www.zdnet.com/zdhelp/stories/main/0,5594,2278598,00.html
Advanced DCC help and information:
http://www.linksys.com/tech_helper/advanced.html
Ok.. that is it for today. Thanks for taking the time to
come to the class. We will see you for the next class here.
If you have any questions concerning todays material (only)
We will now open the channel so you can ask!
Note well: Do not forget to stop logging before you leave
the channel (you may want to log the questions so dont do this
command now (7/log off)
Hello and welcome to our class on DCC.
Since this class is long, and you may want to review
what was said later, Please issue the following command
(in most IRC clients) to start logging the data sent to
the channel,
Please type this now:
/log on
I will start the class with a brief description of
what DCC is, and some of the dangers associated
with using it.
We will then go over the commands associated with DCC
both in general, and ones specific to this network.
Next, we will give some places to look if your having
problems connecting with another user using the DCC protocol
Finally, we will open the channel to a question and answer
session.
Before I go on with this class, I must give credit, where
credit is due. Much of the text in this class is directly
out of the /help function in mIRC. Thanks to the authors
of this very good tool.
DCC stands for "Direct Client to Client"
It is one of the protocols (rules for communication)
suppoted under IRC. When you use DCC you establish a
Direct link between your machine, and the other user of IRC
you are communicating with (bypassing the IRC servers).
DCC allows you to connect directly to another IRC client,
instead of going through the IRC Network,
to Send and Get files, and to Chat privately over a more
secure connection.
We will start this section with a list of the DCC related
commands. Then go into detail on each of them.
Standard DCC Commands:
/dcc chat
/dcc get
/dcc ignore
/dcc nick
/dcc reject
/dcc send
/dcc trust
/dccserver
DALnet specific Commands:
/dccallow
----
The /dcc chat command:
The /dcc chat nickname
This command is a way of initiating a dcc chat, where
nickname is the user with whom you want to dcc chat.
Notes: During this class:
The term 'nickname' should be replaced with the nick you wish
to communicate with.
the /dcc get command:
Command format: /dcc get folder
You can manually redirect an incoming dcc send
to a specific folder with the above command.
This will change the default folder mIRC uses as
the place it stores incomming data from a send by
another user (or fileserver).
note: this is a rarely used command and is an
alternate to using:
alt+o | dcc | folders
( Where alt + o means hold down alt key and press o )
and changing the information there.
the /dcc ignore command:
Accepting or Ignoring files:
This function is used in conjunction with the
setting in DCC Options section of mIRC.
It allows you to accept or ignore automatically
certain filetypes when someone tries to send you a file.
command format: /dcc ignore [on | off | accept | ignore]
/dcc ignore on (turn on auto ignore of filetypes)
/dcc ignore off (turn off auto ignore of filetypes)
/dcc ignore accept (turn off for short period) (note1)
/dcc ignore ignore (turn on for short period) (note1)
(note1): the time period is set in dcc options section of mirc.
WARNING - setting this to anything but ON can leave you open
to receiving virus data!
The /dcc nick command:
This option determines how mIRC behaves if someone changes
nicks during a send, get, or fileserver request.
By default, mIRC will pop up a dialog asking you if you
would like to accept the request in question. However you
can make mIRC automatically accept the request, or just
ignore all incoming requests.
Command format is: /dcc nick -sgcf oldnick newnick
and allows you to change the nickname associated with a
current dcc send/get/chat/fserve request.
The /dcc reject command:
You can manually redirect an incoming dcc send to a specific
folder with /dcc reject
You can use /dcc reject to reject the dcc send.
Note: Both of these commands must be called from within the
CTCP event or the on DCCSERVER send event.
(translation: This function is for use by
acomplished mIRC scripters only <wink>)
The /dcc send command:
The /dcc send command can also be used to initiate
a DCC Send to the specified nickname.
The format of the command is:
/dcc send -cl <nick> file1 file2 fileN
If you specify more than one filename, multiple dcc send
sessions to the specified user are initiated.
If you specify a wildcard filename, then the DCC Send
dialog will display files matching the wildcard.
The -c switch makes the dcc window close automatically
once the transfer has finished.
The -l switch limits the transfer rate to the max cps
limit specified in the 'DCC Fileserver'.
Note: If you want to connect to someone else's DCC Server
you can specify an IP Address and port instead of the
nickname, eg. /dcc send ipaddress:port
The /dcc trust command:
Trusted Users:
This allows you to add a list of trusted nicknames,
addresses, or user levels, from which mIRC will
automatically accept dcc sends.
You can use the format:
/dcc trust -r on | off | nick | address | level
pick either on or off to turn a users trust on or off
Specify either nick or address or level with the command
(but only one of the above) in the command to
change the trust list.
The /dccserver command:
DCC Server
The mIRC DCC Server listens for direct connections to your
IP address from other mIRC clients.
You can change the settings of the DCC Server from
the command line using:
/dccserver +/-scf on | off port
Since this command can make mIRC automatically accept DCC
requests, it should be used with extreme care.
The mIRC FileServer:
There is one other DCC related funtion in mIRC..
This is the FileServer funtion.
The mIRC fileserver allows other users to access
files on your hard disk and is therefore dangerous.
If used improperly, it will allow them to
access private/confidential information.
Due to the above, We will NOT be teaching anything
about how to setup or use the mIRC built in fileServer
in this (or any other) class.
Network specific command(s):
/dccallow command:
In an attempt to further protect users of
DCC functions. Many IRC networks (what mIRC talks to)
have added this command to restict who can send a user
files. It is not unlike the /dcc trust command built
into mIRC, but works at the server level of protcols.
Most IRC Networks that have implemented this command have
inplemented a help function. It can be accessed via:
/dccallow help
(output of the command is displayed in the 'status box)
use is as follows:
/dccallow +nickname (to allow user to send to you)
/dccallow -nickname (to NOT allow user to send to you)
note: Since this is a server level comand, once you leave
a network, the settings are dropped, and you must again do
an allow for trusted users the next time you come on the
network.
Problems connecting with another user using DCC
This section will only touch on the resolution of DCC
connect issues. It will however, point out the areas
that are the 'normal' things (that can be resolved with
a little work). It will point you to URL's that contain
details on how to resolve issues associated with PROXYs,
Firewalls, and also mIRC setup associated with DCC that
could cause problems (with proxy's and firewalls).
The #mIRC channel on most networks is a place users can
go to ask for help with DCC connection issues. However,
the URLs listed in this part of the class should be your
first point of reference (you may want to log this section
of the class if you are not doing so already (7/log on).
Thing we will cover related to DCC problems
Some basics and an overview
IP address: and how it relates to DCC functions
Firewalls: protect... (and get in the way)
Routers: How many computers do you have anyway!
BNC's: You BNC? DCC protocol Doesn't
(you can't have your cake and eat it too!)
Proxy Servers: What a mess they can make of DCC
Things outside your control: Why you can't DCC at School/Work
Most Basic check:
Is your problem with both sending and recieving,
or only with sends?
The ability to recieve, but not send can be caused
by several things, while both being blocked tend to
be caused by ip mismatch or scripts.
Checking for an ip mismatch is easy.
type: /dns yournickname
type: //echo -a $ip7
The two numbers, the one you see when you
type //echo -a $ip, and the other from the
number portion of what you get from typing
/dns yournickname must be the same.
If they arent, type: /localinfo -u
Then check again.
If they are still wrong you may need to disconnect
and in File / Options / Connect / LocalInfo,
clear the local host and ip address boxes.
Check on connect always get local host, and
try using server as the look up method instead
of normal.
IP Address:
Your IP address is your adress on the internet. It is set,
when you connect to the internet, by the Internet Service
Provider (ISP) you connect to.
This information will normally be filled in by mIRC and is
here mainly for your information.
mIRC looks up your IP address and stores it in the mirc.ini
file for future reference.
This way it doesn't have to look it up every time you want
to connect (via DCC).
If mIRC is having trouble getting your IP address
(when you first start mIRC) then you can enter this
value manually and mIRC will assume that it is correct.
If this value is wrong you will still be able to log on to
IRC but you will not be able to initiate DCC Send/Chat
sessions (you will only be able to accept them).
Your Local Host and IP Address are needed if you want to use
the DCC capabilities of mIRC.
for more information on IP Address, in mICR, you can type:
/help ip address
Firewalls:
Firewalls are a very good thing, they give you a great deal of
protection from people who want to do you wrong while on IRC.
However, if they are not configured correctly, DCC functions
will not work.
The concept of how a firewall works is simple... it monitors
your incomming data, you define to it: which ports, addresses,
etc. you wish to allow to get through to you.
So, DCC communications have to be within the range of your
accepted parmameters (for firewall and IRC client), or they
will not get through.
This does NOT mean you can not DCC with a firewall, but it
does mean you will need to configure both mIRC
(or any other IRC client software), and your firewall,
so they can work with DCC.
It also means that the person you establish DCC communicating
with, must also follow the rules you have setup in your
firewall (and irc client).
The configuration of individual firewalls, and mIRC is to
involved a subject to cover in this class. However, the
following link (url address) will help you in this area.
http://www.mirc.org/dcchelp.html
routers:
A router is a hardware and software combination that lets
multiple computers share the same internet connection
(IP address to the internet). It does this by presenting to
the internet multiple psudo addresses for each machine
behind the router. Since these are psudo addresses, the
router must know how to pass data to the individual machine
it was ented to go to (machines on your 'local network')
It is possible to configure mIRC and a router so that
machines behind the router (the local net machines) can
use DCC.
Since the particulars of how to do this are unique to each
of many kinds of routers, we will not address this in the
class but will, rather, privide you with a list of URLs that
will help you with this task (based upon type of router).
While this list is not a complte one, it will cover most of
the most common routers. Here it is:
http://www.mirc.org/dccprob.html
BNC's:
A BNC (sometimes called a bouncer) is a server which lets you
'pass through' to an IRC server. In the process it masks your
true IP address and (in some cases) gives you a fake 'mask'.
Since DCC Protocol depends on accurate IP address information,
DCC functions do not work when you use a BNC. End of story.
Translation: If you want to DCC get/send/chat, do not use a BNC.
Proxy Servers:
Things outside your control:
If you are at school, or at a place of business, you are
almost always on a local area net. Since you do not have
access (or authority) to modify the router in this
environment you normally can not use DCC.
This is done to protect the assets of the school or
business. (And why are you on IRC when you should be
working or hitting the books, anyway <wink>)
URL's for more information on DCC issues:
Here is a fairly comperhensive list of URLs that can
address DCC issues as related to IRC. We hope they
resolve your problems. However, if they do not, please
remember that the operators in #mIRC channel on most
networks can (and will) help you.
basic DCC help:
http://www.mirc.org/dcchelp.html
In depth DCC help:
http://www.mirc.org/dccprob.html
Windows XP Specific:
http://www.mirc.org/xphelp.html
'Wingate' a commonly used windows proxy server:
http://www.deerfield.com/wingate/
Some helpful tips and sample configurations for
using mIRC with ICS, Wingate, and Firewalls:
http://www.borg.com/~chuck/using.htm
Help with Linksys routers (for mIRC client):
http://www.practicallynetworked.com/support/linksys_router_help_pg4.htm#mIRC
13mIRC.com's proxy help:
href="http://www.mirc.co.uk/help/proxies.html
DALnet's proxy help:
http://kline.dal.net/proxy/index.html
TCP/IP books and resources:
http://www.landfield.com/faqs/internet/tcp-ip/resource-list
http://www.books.mfi.com/lan/LANTut3rdEd.html
http://www.wizard.com/users/baker/public_html/NetTutor.html
Information on Send Problems:
http://www.mirc.co.uk/help/sendproblems.html
Conceal Firewall:
http://www.conceal8.com
ZoneAlarm Firewall:
http://www.zonealarm.com
13Info on Cable modems:
http://www.cablemodeminfo.com/cmbasicsx.html-ssi
Help with Cable modems:
http://www.cablemodemhelp.com/
Help with DSL modems
http://www.zdnet.com/zdhelp/stories/main/0,5594,2278598,00.html
Advanced DCC help and information:
http://www.linksys.com/tech_helper/advanced.html
Ok.. that is it for today. Thanks for taking the time to
come to the class. We will see you for the next class here.
If you have any questions concerning todays material (only)
We will now open the channel so you can ask!
Note well: Do not forget to stop logging before you leave
the channel (you may want to log the questions so dont do this
command now
(7/log off)
