Nokia M1122 User Manual
Page 21
M1122 Administrator Manual
E
Copyright Nokia Networks Oy
C33906001SE_00
2-10
supports also ADSL Lite. In the ADSL Lite mode, the maximum line
rates are 1536 kbit/s downstream and 512 kbit/s upstream.
M1122 supports both G.992.1 and G.992.2 ADSL recommendations
defined by ITU-T.
Rate adaptation is done in steps of 32 kbit/s. The ADSL interface of
M1122 functions completely automatically and all configuration
related to the ADSL connection is done at the access multiplexer in the
operator’s premises. The network operator can set the data rates as a
part of the network management functionality provided by Nokia
DSLAM.
2.2.7
Point-to-Point Tunneling Protocol (PPTP)
When PPTP local tunneling is used, a local network client initialises a
PPTP-tunneled PPP connection (VPN) to Nokia M1122. The modem
terminates the tunnel and all data from that terminated local PPTP
tunnel will be forwarded to an assigned ATM VCC by using PPP over
AAL5 encapsulation. Thus, each local PPTP tunnel requires an
equivalent ATM VCC assigned to it restricting the total number of
local PPTP hosts to 8.
Local tunneling is used when there is a need to have one or more
computers connected independently to different networks. For
example, in remote work application, the rest of the family may be
using the common ISP services and one or two family members need to
gain access to their corporate networks. With local tunneling, these
remote workers may be connected to a different network than the rest
of the users.
Local tunneling is activated using the PPTP client running, for
example, in Windows. The destination IP address must be M1122
LAN/VBRIDGE IP address depending on the configuration. PPP
packets within PPTP are mapped to the configured VCC. M1122 has
three different ways to choose the ATM VCC that will be used for
tunneling:
D
Automatic, chooses the first free VCC
D
Chooses the VCC number using C:number, where number is from
1 to 8. C:number is typed after the M1122 IP address in PC’s PPTP
client Connect To window (see Figure 2-5).
D
Chooses the VCC number using N:name, where name is the
VCCx description. N:name is fed after the M1122 IP address.