ZyXEL MAX208M User Manual

Appendix D IP Addresses and Subnetting

The following table is a summary for subnet planning on a network with a 16-bit network number.

Table 72 16-bit Network Number Subnet Planning

NO. BORROWED	SUBNET MASK	NO. SUBNETS	NO. HOSTS PER
HOST BITS			SUBNET
1	255.255.128.0 (/17)	2	32766
2	255.255.192.0 (/18)	4	16382
3	255.255.224.0 (/19)	8	8190
4	255.255.240.0 (/20)	16	4094
5	255.255.248.0 (/21)	32	2046
6	255.255.252.0 (/22)	64	1022
7	255.255.254.0 (/23)	128	510
8	255.255.255.0 (/24)	256	254
9	255.255.255.128 (/25)	512	126
10	255.255.255.192 (/26)	1024	62
11	255.255.255.224 (/27)	2048	30
12	255.255.255.240 (/28)	4096	14
13	255.255.255.248 (/29)	8192	6
14	255.255.255.252 (/30)	16384	2
15	255.255.255.254 (/31)	32768	1

Configuring IP Addresses

Where you obtain your network number depends on your particular situation. If the ISP or your network administrator assigns you a block of registered IP addresses, follow their instructions in selecting the IP addresses and the subnet mask.

If the ISP did not explicitly give you an IP network number, then most likely you have a single user account and the ISP will assign you a dynamic IP address when the connection is established. If this is the case, it is recommended that you select a network number from 192.168.0.0 to 192.168.255.0. The Internet Assigned Number Authority (IANA) reserved this block of addresses specifically for private use; please do not use any other number unless you are told otherwise. You must also enable Network Address Translation (NAT) on the WiMAX Device.

Once you have decided on the network number, pick an IP address for your WiMAX Device that is easy to remember (for instance, 192.168.1.1) but make sure that no other device on your network is using that IP address.

The subnet mask specifies the network number portion of an IP address. Your WiMAX Device will compute the subnet mask automatically based on the IP

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address that you entered. You don't need to change the subnet mask computed by the WiMAX Device unless you are instructed to do otherwise.

Private IP Addresses

Every machine on the Internet must have a unique address. If your networks are isolated from the Internet (running only between two branch offices, for example) you can assign any IP addresses to the hosts without problems. However, the Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of IP addresses specifically for private networks:

10.0.0.0 10.255.255.255

172.16.0.0 172.31.255.255

192.168.0.0 192.168.255.255

You can obtain your IP address from the IANA, from an ISP, or it can be assigned from a private network. If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you with the Internet addresses for your local networks. On the other hand, if you are part of a much larger organization, you should consult your network administrator for the appropriate IP addresses.

Regardless of your particular situation, do not create an arbitrary IP address; always follow the guidelines above. For more information on address assignment, please refer to RFC 1597, Address Allocation for Private Internets and RFC 1466, Guidelines for Management of IP Address Space.

IP Address Conflicts

Each device on a network must have a unique IP address. Devices with duplicate IP addresses on the same network will not be able to access the Internet or other resources. The devices may also be unreachable through the network.

Conflicting Computer IP Addresses Example

More than one device can not use the same IP address. In the following example computer A has a static (or fixed) IP address that is the same as the IP address that a DHCP server assigns to computer B which is a DHCP client. Neither can access the Internet. This problem can be solved by assigning a different static IP

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address to computer A or setting computer A to obtain an IP address automatically.

Figure 122 Conflicting Computer IP Addresses Example

Conflicting Router IP Addresses Example

Since a router connects different networks, it must have interfaces using different network numbers. For example, if a router is set between a LAN and the Internet (WAN), the router s LAN and WAN addresses must be on different subnets. In the following example, the LAN and WAN are on the same subnet. The LAN computers cannot access the Internet because the router cannot route between networks.

Figure 123 Conflicting Computer IP Addresses Example

Conflicting Computer and Router IP Addresses Example

More than one device can not use the same IP address. In the following example, the computer and the router s LAN port both use 192.168.1.1 as the IP address.

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The computer cannot access the Internet. This problem can be solved by assigning a different IP address to the computer or the router s LAN port.

Figure 124 Conflicting Computer and Router IP Addresses Example

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E

Importing Certificates

This appendix shows you how to import public key certificates into your web browser.

Public key certificates are used by web browsers to ensure that a secure web site is legitimate. When a certificate authority such as VeriSign, Comodo, or Network Solutions, to name a few, receives a certificate request from a website operator, they confirm that the web domain and contact information in the request match those on public record with a domain name registrar. If they match, then the certificate is issued to the website operator, who then places it on the site to be issued to all visiting web browsers to let them know that the site is legitimate.

Many ZyXEL products, such as the NSA-2401, issue their own public key certificates. These can be used by web browsers on a LAN or WAN to verify that they are in fact connecting to the legitimate device and not one masquerading as it. However, because the certificates were not issued by one of the several organizations officially recognized by the most common web browsers, you will need to import the ZyXEL-created certificate into your web browser and flag that certificate as a trusted authority.

Note: You can see if you are browsing on a secure website if the URL in your web browser s address bar begins with https:// or there is a sealed padlock icon ( ) somewhere in the main browser window (not all browsers show the padlock in the same location.)

In this appendix, you can import a public key certificate for:

Internet Explorer on page 206

Firefox on page 216

Opera on page 222

Konqueror on page 230

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Appendix E Importing Certificates

Internet Explorer

The following example uses Microsoft Internet Explorer 7 on Windows XP Professional; however, they can also apply to Internet Explorer on Windows Vista.

1If your device s web configurator is set to use SSL certification, then the first time you browse to it you are presented with a certification error.

Figure 125 Internet Explorer 7: Certification Error

2Click Continue to this website (not recommended).

Figure 126 Internet Explorer 7: Certification Error

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3In the Address Bar, click Certificate Error > View certificates.

Figure 127 Internet Explorer 7: Certificate Error

4In the Certificate dialog box, click Install Certificate.

Figure 128 Internet Explorer 7: Certificate

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5In the Certificate Import Wizard, click Next.

Figure 129 Internet Explorer 7: Certificate Import Wizard

6If you want Internet Explorer to Automatically select certificate store based on the type of certificate, click Next again and then go to step 9.

Figure 130 Internet Explorer 7: Certificate Import Wizard

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7Otherwise, select Place all certificates in the following store and then click Browse.

Figure 131 Internet Explorer 7: Certificate Import Wizard

8In the Select Certificate Store dialog box, choose a location in which to save the certificate and then click OK.

Figure 132 Internet Explorer 7: Select Certificate Store

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9In the Completing the Certificate Import Wizard screen, click Finish.

Figure 133 Internet Explorer 7: Certificate Import Wizard

10If you are presented with another Security Warning, click Yes.

Figure 134 Internet Explorer 7: Security Warning

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11Finally, click OK when presented with the successful certificate installation message.

Figure 135 Internet Explorer 7: Certificate Import Wizard

12The next time you start Internet Explorer and go to a ZyXEL web configurator page, a sealed padlock icon appears in the address bar. Click it to view the page s

Website Identification information.

Figure 136 Internet Explorer 7: Website Identification

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Installing a Stand-Alone Certificate File in Internet Explorer

Rather than browsing to a ZyXEL web configurator and installing a public key certificate when prompted, you can install a stand-alone certificate file if one has been issued to you.

1Double-click the public key certificate file.

Figure 137 Internet Explorer 7: Public Key Certificate File

2In the security warning dialog box, click Open.

Figure 138 Internet Explorer 7: Open File - Security Warning

3Refer to steps 4-12 in the Internet Explorer procedure beginning on page 206 to complete the installation process.

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Removing a Certificate in Internet Explorer

This section shows you how to remove a public key certificate in Internet Explorer 7.

1Open Internet Explorer and click TOOLS > Internet Options.

Figure 139 Internet Explorer 7: Tools Menu

2In the Internet Options dialog box, click Content > Certificates.

Figure 140 Internet Explorer 7: Internet Options

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3In the Certificates dialog box, click the Trusted Root Certificates Authorities tab, select the certificate that you want to delete, and then click Remove.

Figure 141 Internet Explorer 7: Certificates

4In the Certificates confirmation, click Yes.

Figure 142 Internet Explorer 7: Certificates

5In the Root Certificate Store dialog box, click Yes.

Figure 143 Internet Explorer 7: Root Certificate Store

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6The next time you go to the web site that issued the public key certificate you just removed, a certification error appears.

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