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Broadband connections in the public phone network

Temporary high-speed or permanent broadband line connection

DSL technology utilizes the existing analog telephone infrastructure. With the world's most extensive network, remote access can be gained to the remotest corners of the globe.

Use the high-speed Internet connection and you can access individual machines, systems or complex Ethernet networks anytime, anywhere in the world.

ADSL broadband routers are ideally suited for short-term high-speed access in the case of servicing (teleservice) as well as for the permanent connection of remote stations to the central company network (permanent broadband line).

The integrated Annex A/B switchover and individual  selection between modem/router functionality offer maximum flexibility. Extensive preliminary clarification of provider requirements is not necessary.

Flexible use in industrial environments

Annex A and B  

Annex A, B and J

The Annex procedure used depends on the provider and features a uniform design in most countries, for example, B and J are predominantly used in Germany (ALL-IP connections of Deutsche Telekom). Annex A and Annex B are most commonly used worldwide.

  • Annex A: DSL operation parallel to analog telephony.
  • Annex B: DSL operation parallel to digital telephony (ISDN/Integrated Services Digital Network)
  • Annex J: IP-based connections (ALL-IP connections of Deutsche Telekom)

Thanks to integrated Annex A/B switchover, broadband routers from Phoenix Contact can be easily adapted to the requirements of regional telecommunications providers.  

Most commonly Annex A and Annex B

CountryAnnex A/B
BelgiumMixed, primarily Annex A
DenmarkMixed, primarily Annex A
GermanyAnnex B and Annex J
FranceMixed, primarily Annex A
Great BritainAnnex A
IcelandAnnex A
ItalyMixed, primarily Annex A
NetherlandsMixed, primarily Annex A
North AmericaAnnex A
NorwayMixed, primarily Annex B
AustriaMixed, primarily Annex A
SwedenMixed, primarily Annex A
SwitzerlandAnnex B
SpainMixed, primarily Annex A

Modem mode

The DSL modem handles the signal conditioning between the public DSL and the local network. The router and firewall functions are handled by a downstream router, e.g., a security router or mobile router.

VPN tunnel with DSL modem  

Use as a DSL modem in combination with a security router (e.g., FL MGUARD).

VPN tunnel with DSL modem and mobile router  

Use as a DSL modem in combination with a security router (e.g., FL MGUARD) or mobile router (e.g., PSI-MODEM-3G/ROUTER).

Router mode

The broadband router handles not only the signal conditioning from DSL to LAN (DSL modem) but also the actual router, VPN, and NAT functions.

VPN tunnel with DSL router  

Use as a DSL router – the VPN router and firewall functions are handled by the DSL devices themselves.

Application-based device types

Use the device type best suited to your application.

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Further information
  • Broadband connections in the public phone network


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