ZyNOS FAQ
2. What is the default console port baud rate? How do change it?
The default console port baud rate is 9600bps. When configuring,
please make sure the terminal baud rate is also 9600bps. You can change the
console baud rate from 9600bps to 115200bps.
3. How do I upload
the ZyNOS firmware code via console?
The procedure for uploading ZyXEL device via console is as follows.
4. How do I upgrade/backup the ZyNOS firmware by using TFTP client program via LAN?
The ZyXEL device allows you to transfer the firmware from/to ZyXEL device by using TFTP program via LAN. The procedure for uploading ZyNOS via TFTP is as follows.
5. How do I upload ROMFILE via console port?
In some situations, you may need to upload the ROMFILE, such as losing the system password, or the need of resetting to factory default.
The procedure for uploading ROMFILE via the console port is as follows.
6. Why can't I make Telnet to ZyXEL device from WAN?
There are three reasons that Telnet from WAN is blocked.
Source IP= Telnet host
Destination IP= P-335 Plus's WAN IP
Service= TCP/23
Action=Forward
7. What should I do
if I forget the system password?
In case you forget the system password, you need to upload
ROMFILE to reset to factory default. After uploading ROMFILE, the default
system password is '1234'.
8. What is SUA?
When should I use SUA?
SUA (Single User Account) is a unique feature supported by ZyXEL router which allows multiple people to access Internet concurrently for the cost of a single user account.
When ZyXEL device acting as SUA receives a packet from a
local client destined for the outside Internet, it replaces the source
address in the IP packet header with
9. What is the difference between NAT and SUA?
NAT is a generic name defined in RFC 1631 'The IP Network
Address Translator (NAT)'.
SUA (Internet Single User Account) is ZyXEL device's implementation and trade
name for functioning PAT which is a specific type of NAT. SUA(
or PAT for NAT) translates address into port mapping.
The primary motivation for RFC 1631 is that there is not enough IP address to go around. In addition, many corporations simply did not bother to obtain legal (globally unique) IP addresses for their networks and now finding themselves unable to connect to the Internet.
Basically, NAT is a process of translating one address to another. A NAT implementation can be as simple as substituting an IP address with another. This allows a network to rectify the illegal address problem mentioned above without going through each and every host.
The design goal of ZyXEL device's SUA is to minimize the
Internet access cost in a small office environment by using a single IP address
to represent the multiple hosts inside. It does more than IP address
translation, so that multiple hosts on the LAN can access the Internet at the
same time.
10. How many
network users can the SUA/NAT support?
The ZyXEL device does not limit the number of the users but
the number of the sessions. The ZyXEL device 335 supports 2048 sessions that
you can use the 'ip nat
iface enif1' command to view the current
active sessions.
11. What are
Device filters and Protocol filters?
In ZyNOS, the filters have been
separated into two groups. One group is called 'device filter group', and
the other is called 'protocol filter group'. Generic filters belong to
the 'device filter group', TCP/IP and IPX filters belong to the 'protocol
filter group'.
12. Why
can't I configure device filters or protocol filters?
In ZyNOS, you can not mix
different filter groups in the same filter set.
13. How can I
protect against IP spoofing attacks?
The P-335 Plus’s firewall will automatically detect the IP spoofing and drop it if the firewall is turned on. If the firewall is not turned on we can configure a filter set to block the IP spoofing attacks. The basic scheme is as follows:
For the input data filter:
Filter rule setup:
Where a.b.c.d is an IP address on your local network and w.x.y.z is your netmask:
For the output data filters:
Filter rule setup:
Where a.b.c.d is an IP address on your local network and w.x.y.z is your netmask.
All contents copyright (c) 2006 ZyXEL Communications Corporation.