Security 8-67

By matching on a port number, an IP filter can be applied to selected services, such as Telnet, FTP, and World Wide Web. The tables below show a few common services and their associated port numbers.

Internet service

TCP port

Internet service

TCP port

 

 

 

 

 

 

 

 

FTP

20/21

Finger

79

 

 

 

 

Telnet

23

World Wide Web

80

 

 

 

 

SMTP (mail)

25

News

144

 

 

 

 

Gopher

70

rlogin

513

 

 

 

 

 

 

 

 

Internet service

UDP port

Internet service

UDP port

 

 

 

 

 

 

 

 

Who Is

43

AppleTalk Routing

202

 

 

Maintenance (at-rtmp)

 

 

 

 

 

World Wide Web

80

AppleTalk Name Binding

202

 

 

(at-nbp)

 

 

 

 

 

SNMP

161

AURP (AppleTalk)

387

 

 

 

 

TFTP

69

who

513

 

 

 

 

Port number comparisons

An IP filter can also use a comparison option to evaluate a packet’s source or destination port number. The comparison options are:

No Compare: No comparison of the port number specified in the filter with the packet’s port number.

Not Equal To: For the filter to match, the packet’s port number cannot equal the port number specified in the filter.

Less Than: For the filter to match, the packet’s port number must be less than the port number specified in the filter.

Less Than or Equal: For the filter to match, the packet’s port number must be less than or equal to the port number specified in the filter.

Equal: For the filter to match, the packet’s port number must equal the port number specified in the filter.

Greater Than: For the filter to match, the packet’s port number must be greater than the port number specified in the filter.

Greater Than or Equal: For the filter to match, the packet’s port number must be greater than or equal to the port number specified in the filter.

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Netopia D3232 IDSL, D7171 SDSL, D7100 SDSL, D3100-I IDSL manual Ftp, Port number comparisons

D7100 SDSL, D3232 IDSL, D3100-I IDSL, D7171 SDSL specifications

Netopia offers a range of advanced digital subscriber line (DSL) modems that cater to various connectivity needs. Among these, the D7171 SDSL, D3100-I IDSL, D3232 IDSL, and D7100 SDSL models stand out for their robust features and technologies designed to enhance the user experience.

The Netopia D7171 SDSL modem is engineered for symmetrical digital subscriber line (SDSL) services, delivering equal upload and download speeds. It supports high-speed data transfers over standard copper lines, enabling businesses to maintain consistent performance for applications such as video conferencing and large file transfers. Key features of the D7171 include enhanced security protocols, a built-in firewall to protect against unauthorized access, and multiple interface options for flexible connectivity.

Moving to the D3100-I IDSL, this model caters to users who require a reliable internet connection over a longer distance than traditional DSL can provide. The IDSL technology enables it to function effectively in areas where standard DSL is unavailable or unreliable. It provides a lower bandwidth solution yet is valuable in reaching remote locations. This modem is particularly recognized for its ease of installation and robust performance, featuring built-in diagnostics that help troubleshoot potential connection issues.

In the same family, the D3232 IDSL offers similar advantages but with a focus on higher capacity and scalability. It is designed for small to medium enterprises that require greater bandwidth for multiple users or devices. This modem also supports both voice and data transmission, making it an attractive option for unified communications. The D3232 comes equipped with advanced networking features, including Quality of Service (QoS) capabilities to prioritize bandwidth for critical applications.

Lastly, the D7100 SDSL modem is distinguished by its versatility and high-performance output. Supporting SDSL standards, it is perfect for businesses that need reliable, symmetrical speeds. This model is characterized by its extensive range of connectivity options, including Ethernet ports and support for various network protocols, ensuring seamless integration into existing network infrastructures. Additionally, it boasts excellent reliability, making it a favored choice for mission-critical applications.

In summary, Netopia's DSL modems, including the D7171 SDSL, D3100-I IDSL, D3232 IDSL, and D7100 SDSL, provide scalable and reliable internet connectivity solutions tailored to meet diverse business needs. With cutting-edge technology and a suite of features designed for performance, these models are well-suited to enhance productivity and support modern communications.