&nbsp;<br />
<b><big>Frequently Asked Questions</big></b>
<br />&nbsp;<br />
<a href="#f1_0" class="normal">1. General Questions</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_10" class="normal">1.1 What is SILC?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_20" class="normal">1.2 When was SILC Project started?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_30" class="normal">1.3 Why SILC in the first place?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_40" class="normal">1.4 What license covers the SILC release?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_50" class="normal">1.5 Why SILC? Why not IRC3?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_55" class="normal">1.6 What platforms SILC supports?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_60" class="normal">1.7 Where can I find more information?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f1_70" class="normal">1.8 I would like to help out, what can I do?</a>
<br />&nbsp;<br />
<a href="#f2_0" class="normal">2. Protocol Questions</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_10" class="normal">2.1 What is the status of SILC protocol in the IETF?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_20" class="normal">2.2 How much the SILC protocol is based on IRC?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_30" class="normal">2.3 Why use SILC? Why not IRC with SSL?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_40" class="normal">2.4 Can I talk from SILC network to IRC network?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_45" class="normal">2.5 Does SILC support file transfer?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_47" class="normal">2.6 I am behind a firewall, can I use SILC?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_50" class="normal">2.7 How secure SILC really is?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_60" class="normal">2.8 Does SILC support instant messaging?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_70" class="normal">2.9 Why SILC does not have LINKS command like in IRC?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_80" class="normal">2.10 Why SILC does not have STATS command like in IRC?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f2_90" class="normal">2.11 I have suggestions to SILC Protocol, what can I do?</a>
<br />&nbsp;<br />
<a href="#f3_0" class="normal">3. Client Questions</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f3_10" class="normal">3.1 Where can I find SILC clients?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f3_20" class="normal">3.2 Can I use SILC with IRC client and vice versa?</a>
<br />&nbsp;<br />
<a href="#f4_0" class="normal">4. Server Questions</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f4_10" class="normal">4.1 Where can I find SILC servers?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f4_20" class="normal">4.2 Can I run own SILC server?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f4_30" class="normal">4.3 What is the difference between SILC server and SILC router?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f4_40" class="normal">4.4 Why server says permission denied to write to a log file?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f4_50" class="normal">4.5 When I connect to to my server, it says "server does not support one of your proposed cipher", what is wrong?</a>
<br />&nbsp;<br />
<a href="#f5_0" class="normal">5. Toolkit Questions</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f5_10" class="normal">5.1 What is SILC Toolkit?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f5_20" class="normal">5.2 Is the SILC Toolkit Reference Manual Available?</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f5_30" class="normal">5.3 How do I compile the Toolkit on Unix</a><br />
 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#f5_40" class="normal">5.4 How do I compile the Toolkit on Win32</a><br />
<br />&nbsp;<br />

<a name="f1_0"></a>
<b>1. General Questions</b><br />&nbsp;<br />

<a name="f1_10"></a>
<samp class="blue">Q: What is SILC?</samp><br />
A: SILC (Secure Internet Live Conferencing) is a protocol which provides
secure conferencing services in the Internet over insecure channel. SILC
is IRC like although internally they are very different. Biggest
similarity between SILC and IRC is that they both provide conferencing
services and that SILC has almost same commands as IRC. Other than that
they are nothing alike.
<br />&nbsp;<br />
Biggest differences are that SILC is secure what IRC is not in any way.
The network model is also entirely different compared to IRC.
<br />&nbsp;<br />

<a name="f1_20"></a>
<samp class="blue">Q: When was SILC Project started?</samp><br />
A: The SILC development started in 1996 and early 1997. But, for various 
reasons it suspended many times until it finally got some wind under its 
wings in 1999. First public release was in summer 2000.
<br />&nbsp;<br />

<a name="f1_30"></a>
<samp class="blue">Q: Why SILC in the first place?</samp><br />
A: Simply for fun, nothing more. And actually for need back in the days
when it was started. When SILC was first developed there really did not 
exist anything like this. SILC has been very interesting and educational 
project.
<br />&nbsp;<br />

<a name="f1_40"></a>
<samp class="blue">Q: What license covers the SILC release?</samp><br />
A: The SILC software developed here at silcnet.org, the SILC Client, the 
SILC Server and the SILC Toolkit are covered by the GNU General Public 
License.
<br />&nbsp;<br />

<a name="f1_50"></a>
<samp class="blue">Q: Why SILC? Why not IRC3?</samp><br />
A: Question that is justified no doubt of that. SILC was not started to 
become a replacement for IRC. SILC was something that didn't exist in 1996 
or even today except that SILC is now released. However, I did check out 
the IRC3 project in 1997 when I started coding and planning the SILC protocol.
<br />&nbsp;<br />
But, IRC3 is problematic. Why? Because it still doesn't exist. The
project is almost at the same spot where it was in 1997 when I checked it 
out. And it was old project back then as well. That's the problem of IRC3 
project. The same almost happened to SILC as well as I wasn't making real 
progress over the years. I talked to the original author of IRC, Jarkko 
Oikarinen, in 1997 and he directed me to the IRC3 project, although he 
said that IRC3 is a lot of talking and not that much of anything else. I 
am not trying to put down the IRC3 project but its problem is that no one 
in the project is able to make a decision what is the best way to go about
making the IRC3 and I wasn't going to be part of that. The fact is that
if I would've gone to IRC3 project, nor IRC3 or SILC would exist today. I
think IRC3 could be something really great if they just would get their
act together and start coding the thing.
<br />&nbsp;<br />

<a name="f1_55"></a>
<samp class="blue">Q: What platforms SILC supports?</samp><br />
A: The SILC Client is available on various Unix systems and is reported to 
work under cygwin on Windows. The SILC Server also works on various Unix 
systems. However, the server has not been tested under cygwin as far as we 
know. The SILC Toolkit is distributed for all platforms, Unix, Cygwin 
and native Windows.
<br />&nbsp;<br />

<a name="f1_60"></a>
<samp class="blue">Q: Where can I find more information?</samp><br />
A: For more technical information we suggest reading the SILC Protocol 
specifications. You might also want to take a look at the <a 
href="?page=docs" class="normal">documentation </a> page on the web page.
<br />&nbsp;<br />

<a name="f1_70"></a>
<samp class="blue">Q: I would like to help out, what can I do?</samp><br />
A: You might want to take a look at the <a 
href="?page=contribute" class="normal">Contributing</a> page and the <a 
href="?page=todo" class="normal">TODO</a> list. You might also want to join the 
SILC development mailing list.
<br />&nbsp;<br />

<a name="f2_0"></a><br />
<b>2. Protocol Questions</b><br />&nbsp;<br />

<a name="f2_10"></a>
<samp class="blue">Q: What is the status of SILC protocol in the IETF?</samp><br />
A: The SILC protocol specifications has been submitted currently as 
individual submissions. There does not currently exist a working group 
for this sort of project. Our goal is to fully standardize the SILC and 
thus submit it as RFC to the <a href="http://www.ietf.org/" class="normal">IETF</a> at a 
later time.
<br />&nbsp;<br />

<a name="f2_20"></a>
<samp class="blue">Q: How much SILC Protocol is based on IRC?</samp><br />
A: SILC is not based on IRC. The client superficially resembles IRC 
client but everything that happens under the hood is nothing alike IRC. 
SILC could *never* support IRC because the entire network toppology is 
different (hopefully more scalable and powerful). So no, SILC protocol 
(client or server) is not based on IRC. Instead, We've taken good things 
from IRC and left all the bad things behind and not even tried to burden 
the SILC with the IRCs problems that will burden IRC and future IRC 
projects till the end. SILC client resembles IRC client because it is 
easier for new users to start using SILC when they already know all the 
commands.
<br />&nbsp;<br />

<a name="f2_30"></a>
<samp class="blue">Q: Why use SILC? Why not IRC with SSL?</samp><br />
A: Sure, that is possible, although, does that secure the entire IRC
network? And does that increase or decrease the lags and splits in the 
IRC network? Does that provide user based security where some specific 
private message are secured? Does that provide security where some 
specific channel messages are secured? And I know, you can answer yes to 
some of these questions. But, security is not just about applying 
encryption to traffic and SILC is not just about `encrypting the 
traffic`. You cannot make insecure protocol suddenly secure just by 
encrypting the traffic. SILC is not meant to be IRC replacement. IRC is 
good for some things, SILC is good for same and some other things.
<br />&nbsp;<br />

<a name="f2_40"></a>
<samp class="blue">Q: Can I talk from SILC network to IRC network?</samp><br />
A: Simple answer for this is No. The protocols are not compatible which 
makes it impossible to directly talk from SILC network to IRC network or 
vice versa. Developing a gateway between these two networks would 
technically be possible but from security point of view strongly not 
recommended. We have no plans for developing such a gateway.
<br />&nbsp;<br />

<a name="f2_45"></a>
<samp class="blue">Q: Does SILC support file transfer?</samp><br />
A: Yes.  The SILC protocol support SFTP as mandatory file transfer 
protocol.  It provides simple client to client file transfer, but also
a possibility for file and directory manipulation.  Even though the SFTP
is the file transfer protocol the support for file transferring has been 
done so that practically any file transfer protocol may be used with SILC 
protocol.
<br />&nbsp;<br />

<a name="f2_47"></a>
<samp class="blue">Q: I am behind a firewall, can I use SILC?</samp><br />
A: Yes. If your network administrator can open the port 706 (TCP) you can 
use SILC without problems. You may also compile your SILC client with 
SOCKS support which will proxy your SILC session through the firewall.
<br />&nbsp;<br />

<a name="f2_50"></a>
<samp class="blue">Q: How secure SILC really is?</samp><br />
A: A good question which I don't have an answer for. We have tried to make
SILC as secure as possible. However, there is no security protocol or
security software that has not been vulnerable to some sort of attacks.
SILC is in no means different from this. So, it is suspected that there
are security holes in the SILC. These holes just need to be found so
that they can be fixed.
<br />&nbsp;<br />
But to give you some parameters of security SILC uses the most secure
crytographic algorithms such as AES(Rijndael), Twofish, Blowfish, RC5,
etc. SILC does not have DES or 3DES as DES is insecure and 3DES is just
too slow. SILC also uses cryptographically strong random number generator
when it needs random numbers. Public key cryptography uses RSA (PKCS #1)
and Diffie-Hellman algorithms. Key lengths for ciphers are initially set
to 256. For public key algorithms the starting key length is 1024 bits.
<br />&nbsp;<br />
But the best answer for this question is that SILC is as secure as its
weakest link. SILC is open and the protocol is open and in public thus
open for security analysis.
<br />&nbsp;<br />
To give a list of attacks that are ineffective against SILC:
<br />&nbsp;<br />
- Man-in-the-middle attacks are ineffective if proper public key
infrastructure is used. SILC is vulnerable to this attack if the public
keys used in the SILC are not verified to be trusted (as any other
protocol for that matter).<br />
 - IP spoofing is ineffective (because of encryption and trusted keys).<br />
 - Attacks that change the contents of the data or add extra data to the
packets are ineffective (because of encryption and integrity checks).<br />
 - Passive attacks (listenning network traffic) are ineffective (because
of encryption). Everything is encrypted including authentication data
such as passwords when they are needed.<br />
 - Any sort of cryptanalytic attacks are tried to make ineffective by
using the best cryptographic algorithms out there.
<br />&nbsp;<br />

<a name="f2_60"></a>
<samp class="blue">Q: Does SILC support instant messaing?</samp><br />
A: SILC is not an instant message (IM) system, like ICQ and the others. 
SILC is more IRC like system, "real-time", connection-oriented chat and 
that kind of stuff.  But I guess IRC is too called an Instant Messaging 
system.
<br />&nbsp;<br />

<a name="f2_70"></a>
<samp class="blue">Q: Why SILC does not have LINKS command like in 
IRC?</samp><br />
A: It was felt that this information as an own command in SILC is not 
necessary.  Moreover, the topology of the network might be undisclosed 
information even though the servers and routers in the network are still 
open. We feel that the network topology information, if it is wanted to be 
public, and the list of accessible servers can be made available in other 
ways than providing command like LINKS, which shows the active server 
links in IRC.
<br />&nbsp;<br />

<a name="f2_80"></a>
<samp class="blue">Q: Why SILC does not have STATS command like in  
IRC?</samp><br />
A: This too was considered as information that the protocol should not 
address. We feel that server implementations will need to implement some 
sort of adminstrative plugin, or module which provides various means of 
accessing statistical and other information in the server. And, we do 
consider this implementation issue, not protocol design issue.
<br />&nbsp;<br />

<a name="f2_90"></a>
<samp class="blue">Q: I have suggestions to SILC Protocol, 
what can I do?</samp><br />
A: All suggestions and improvements are of course welcome. You should read 
the protocol specifications first to check out whether your idea is 
covered by them already. The best place to make your idea public is the 
SILC development mailing list.
<br />&nbsp;<br />


<a name="f3_0"></a><br />
<b>3. Client Questions</b><br />&nbsp;<br />

<a name="f3_10"></a>
<samp class="blue">Q: Where can I find SILC clients?</samp><br />
A: The SILC client is available for free download from the silcnet.org web 
page. Some people have also mentioned words Java and Perl when talking 
about SILC clients. Nothing has appeared yet, though.
<br />&nbsp;<br />

<a name="f3_20"></a>
<samp class="blue">Q: Can I use SILC with IRC client and vice versa?</samp><br />
A: Generally the answer would be no for both. However, there exist already 
at least one IRC client that supports SILC, the <a 
href="http://irssi.org/" class="normal">Irssi client</a>. The current SILC client is 
actually based on the user interface of the Irssi client. So, yes it is 
possible to use SILC with some IRC clients and vice versa. But, this 
does not mean that you can talk from SILC network to IRC network, that is 
not possible.
<br />&nbsp;<br />

<a name="f4_0"></a><br />
<b>4. Server Questions</b><br />&nbsp;<br />

<a name="f4_10"></a>
<samp class="blue">Q: Where can I find SILC servers?</samp><br />
A: The SILC server is available for free download from the silcnet.org 
web page. We are not aware of any other SILC server implementations, so far.
<br />&nbsp;<br />

<a name="f4_20"></a>
<samp class="blue">Q: Can I run own SILC server?</samp><br />
A: Yes of course. Download the SILC server package, compile and install 
it. Be sure to check out the installation instructions and the README 
file. You also should decide whether you want to run SILC server or SILC 
router.
<br />&nbsp;<br />

<a name="f4_30"></a>
<samp class="blue">Q: What is the difference between SILC 
server and SILC router?</samp><br />
A: The topology of the SILC network includes SILC routers and the SILC 
servers (and SILC clients of course). Normal SILC server does not have 
direct connections with other SILC servers. They connect directly to the 
SILC router. SILC Routers may have several server connections and they 
may connect to several SILC routers. The SILC routers are the servers in 
the network that know everything about everything. The SILC servers know 
only local information and query global information from the router when 
necessary.
<br />&nbsp;<br />
If you are running SILC server you want to run it as router only if you 
want to have server connections in it and are prepared to accept server 
connections. You also need to get the router connected to some other 
router to be able to join the SILC network. You may run the server as 
normal SILC server if you do not want to accept other server connections 
or cannot run it as router.
<br />&nbsp;<br />

<a name="f4_40"></a>
<samp class="blue">Q: Why server says permission denied to write to a 
log file?</samp><br />
A: The owner of the log files must be same user that the server is run 
under, by default it is user `nobody'.  Just change the permissions and 
try again.
<br />&nbsp;<br />

<a name="f4_50"></a>
<samp class="blue">Q: When I connect to my server it says "server does 
not support one of your proposed ciphers", what is wrong?</samp><br />
A: Most likely the ciphers and others has not been compiled as SIMs 
(modules) and they are configured as modules in the silcd.conf. If they 
are not compiled as modules remove the module paths from the ciphers and 
hash functions from the silcd.conf, so that the server use the builtin 
ciphers. Then try connecting to the server again. It is also possible 
that the client IS proposing some ciphers that your server does not support.
<br />&nbsp;<br />


<a name="f5_0"></a><br />
<b>5. Toolkit Questions</b><br />&nbsp;<br />

<a name="f5_10"></a>
<samp class="blue">Q: What is SILC Toolkit?</samp><br />
A: SILC Toolkit is a package intended for software developers who would 
like to develope their own SILC based applications or help in the 
development of the SILC. The Toolkit includes SILC Protocol Core library, 
SILC Crypto library, SILC Key Exchange (SKE) library, SILC Math 
library, SILC Modules (SIM) library, SILC Utility library, SILC Client 
library and few other libraries. 
<br />&nbsp;<br />

<a name="f5_20"></a>
<samp class="blue">Q: Is the SILC Toolkit Reference Manual Available?</samp><br />
A: Yes, partially completed reference manual is available in the Toolkit 
releases as HTML package and they are available from the silcnet.org 
website as well at the <a href="?page=docs" class="normal">documentation </a> page.
<br />&nbsp;<br />

<a name="f5_30"></a>
<samp class="blue">Q: How do I compile the Toolkit on Unix?</samp><br />
A: You should read the INSTALL file from the package and follow its 
instructions.  The compilation on Unix is as simple as compiling any other 
SILC package.  Give, `./configure' command and then `make' command.
<br />&nbsp;<br />

<a name="f5_40"></a>
<samp class="blue">Q: How do I compile the Toolkit on Win32?</samp><br />
A: We have prepared instructions to compile the Toolkit on Win32 in the 
Toolkit package.  Please, read the README.WIN32 file from the package for 
detailed instructions how to compile the Toolkit for Cygwin, MinGW and 
native Win32 systems.  We have also prepared ready MSVC++ Workspace files 
in the win32/ directory in the package that will compile automatically 
the Toolkit.
<br />&nbsp;<br />