не понимаю как настроить данный сабж на совместную работу...
вот конфиг CISCO, со стороны D-LINK настройки сделаны согласно FAQ

-----
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname 77-PYT-C2801
!
boot-start-marker
boot-end-marker
!
logging buffered 51200 warnings
logging console critical
enable secret 5 АААА
!
no aaa new-model
clock timezone MOSCOW 3
clock summer-time MOSCOW recurring last Sun Mar 2:00 last Sun Oct 2:00
ip cef
!
!
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
no ip dhcp use vrf connected
ip dhcp excluded-address 10.77.77.1 10.77.77.100
!
ip dhcp pool sdm-pool
import all
network 10.77.77.0 255.255.255.0
default-router 10.77.77.1
dns-server 195.54.192.ЕЕ
lease 0 2
!
!
no ip domain lookup
ip domain name 77-pyt-c851
ip name-server 195.54.192.ЕЕ
vpdn enable
!
vpdn-group 1
! Default L2TP VPDN group
! Default PPTP VPDN group
accept-dialin
protocol any
virtual-template 1
local name pptp_gateway
!
!
!
!
!
username КК password 7 ЕЕЕ
!
!
!
crypto isakmp policy 10
encr 3des
hash md5
authentication pre-share
group 2
crypto isakmp key kakdshfg47 address 91.205.146.АА
!
!
crypto ipsec transform-set SAMPLE_SET esp-3des esp-sha-hmac
!
crypto map DI-804HV 10 ipsec-isakmp
description Description of the crypto map statement policy
set peer 91.205.146.АА
set security-association lifetime seconds 28800
set transform-set SAMPLE_SET
set pfs group2
match address 101
!
!
!
interface FastEthernet0/0
ip address 10.77.77.1 255.255.255.0
ip nat inside
ip virtual-reassembly
ip tcp adjust-mss 1452
duplex auto
speed auto
pppoe enable group global
!
interface FastEthernet0/1
mac-address 00e0.db09.d273
ip address 195.91.152.ЕЕ 255.255.255.248
ip nat outside
no ip virtual-reassembly
duplex auto
speed auto
crypto map DI-804HV
!
interface Virtual-Template1
ip unnumbered FastEthernet0/1
ip mtu 1492
ip nat inside
ip virtual-reassembly
peer default ip address pool REM-CON
no keepalive
ppp authentication chap
!
ip local pool REM-CON 10.77.77.205 10.77.77.250
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 195.91.152.ЕЕ
ip route 10.50.77.0 255.255.255.0 FastEthernet0/1
!
no ip http server
no ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
ip nat inside source list NAT interface FastEthernet0/1 overload
!
ip access-list extended NAT
permit ip 10.50.1.0 0.0.0.255 any
!
ip radius source-interface FastEthernet0/0
access-list 101 permit ip 10.77.77.0 0.0.0.255 10.50.77.0 0.0.0.255
access-list 101 permit ip 10.55.77.0 0.0.0.255 10.77.77.0 0.0.0.255
!
!
control-plane
[...]

В кошачьих конфигах не очень разбираюсь, поэтому поясните, какой именно тип VPN?

_________________
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Разобрался, никгде в примерах/факах не написано, что надо последний релиз прошивки дльиника залить...

в названии темы указали GRE, а поднимаете IPSEC...