EP0838930A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Pseudo network adapter for frame capture, encapsulation and encryption
Assignee: Compaq Computer Corp
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Filing: 1997-10-24
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Granted: —
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Expires: 2017-10-24
Abstract
Abstract A new pseudo network adapter provides an interface for capturing packets from a local communications protocol stack for transmission on the virtual private network, and includes a Dynamic Host Configuration Protocol (DHCP) server emulator, and an Address Resolution Protocol (ARP) server emulator. The new system indicates to the local communications protocol stack that nodes on a remote private network are reachable through a gateway that is in turn reachable through the pseudo network adapter. A transmit path in the system processes data packets from the local communications protocol stack for transmission through the pseudo network adapter. An encryption engine encrypts the data packets and an encapsulation engine encapsulates the encrypted data packets into tunnel data frames. The network adapter further includes an interface into a transport layer of the local communications protocol stack for capturing received data packets from the remote server node, and a receive path for processing received data packets captured from the transport layer of the local communications protocol stack. The receive path includes a decapsulation engine, and a decryption engine, and passes the decrypted, decapsulated data packets back to the local communications protocol stack for delivery to a user.
Inventors
- 👤 Kenneth F. Alden
- 👤 Mitchell P. Lichtenberg
- 👤 Edward P. Wobber
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 16:23
CPC Classifications
H; H04; H04L; H04L61/00; H04L61/09; H04L61/10; H04L61/103; H04L61/50; H04L61/5007; H04L61/5014; H04L63/00; H04L63/02; H04L63/0272; H04L63/04; H04L63/0428; H04L63/0485; H04L63/12; H04L63/123
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
191 words
A pseudo network adapter providing a virtual private
network, comprising: an interface for capturing packets from a local
communications protocol stack for transmission on said
virtual private network, said interface appearing to
said local communications protocol stack as a network
adapter device driver for a network adapter connected
to said virtual private network; a first server emulator, providing a first reply
packet responsive to a first request packet captured
by said interface for capturing packets from said
local communications protocol stack for transmission
on said virtual private network, said first request
packet requesting a network layer address for said
pseudo network adapter, said first reply indicating a
network layer address for said pseudo network adapter;
and a second server emulator, providing a second
reply packet responsive to an second request packet
captured by said interface for capturing packets from
said local communications protocol stack for
transmission on said virtual private network, said
second request packet requesting a physical address
corresponding to a network layer address of a second
pseudo network adapter, said second pseudo network
adapter located on a remote server node, said second
reply indicating a predetermined, reserved physical
address.
Claim 2
Dependent Claim
62 words
The pseudo network adapter of claim 1, further
comprising a means for indicating to said local
communications protocol stack that said predetermined,
reserved physical address is reachable through said pseudo
network adapter, wherein said means for indicating modifies
a data structure in said local communications protocol
stack indicating which nodes or networks are reachable
through each network interface of the local system.
Claim 3
Dependent Claim
53 words
The pseudo network adapter of claim 1, further
comprising a means for indicating to said local
communications protocol stack that one or more nodes on a
remote private network connected to said remote server node
are reachable through a gateway node equal to said second
pseudo network adapter on said remote server node.
Claim 4
Dependent Claim
93 words
The pseudo network adapter of claim 1, further
comprising: a transmit path for processing data packets
captured by said interface for capturing packets from
said local communications protocol stack for
transmission on said virtual private network; an encryption engine, within said transmit path,
for encrypting said data packets; an encapsulation engine, within said transmit
path, for encapsulating said encrypted data packets
into tunnel data frames; and a means for passing said tunnel data frames back
to said local communications protocol stack for
transmission to a physical network adapter on said
remote server node.
Claim 5
Dependent Claim
74 words
The pseudo network adapter of claim 4, wherein said
transmit path further includes means for storing a digest
value in a digest field in each of said tunnel data frames,
said digest value equal to an output of a keyed hash
function applied to said data packet encapsulated within
said tunnel data frame concatenated with a counter value
equal to a total number of tunnel data frames previously
transmitted to said remote server node.
Claim 6
Dependent Claim
38 words
The pseudo network adapter of claim 4, wherein said
transmit path further includes means for processing an
Ethernet header in each one of said captured data packets,
said processing of said Ethernet header including removing
said Ethernet header.
Claim 7
Dependent Claim
31 words
The pseudo network adapter of claim 1, further
comprising: an interface into a transport layer of said local
communications protocol stack for capturing received
data packets from said remote server node.
Claim 8
Dependent Claim
94 words
The pseudo network adapter of claim 7, further
comprising: a receive path for processing received data
packets captured by said interface into said transport
layer of said local communications protocol stack for
capturing received data packets from said remote
server node; an decapsulation engine, within said receive
path, for decapsulating said received data packets by
removing a tunnel frame header; an decryption engine, within said receive path,
for decrypting said received data packets; and a means for passing said received data packets
back to said local communications protocol stack for
delivery to a user.
Claim 9
Independent Claim
189 words
A method for providing a pseudo network adapter for a
virtual private network, comprising the steps of: capturing packets from a local communications
protocol stack for transmission on said virtual
private network, said capturing through an interface
appearing to said local communications stack as a
network adapter device driver for a network adapter
connected to said virtual private network; issuing a first reply packet responsive to a
first request packet captured by said interface for
capturing packets from said local communications
protocol stack for transmission on said virtual
private network, said first request packet requesting
a network layer address for said pseudo network
adapter, said first reply indicating a network layer
address for said pseudo network adapter; and issuing a second reply packet responsive to a
second request packet captured by said interface for
capturing packets from said local communications
protocol stack for transmission on said virtual
private network, said second request packet
requesting a physical address corresponding to a
network layer address of a second pseudo network
adapter, said second pseudo network adapter located on
a remote server node, said ARP Reply indicating a
predetermined, reserved physical address.
Claim 10
Dependent Claim
63 words
The method of claim 9, further comprising indicating
to said local communications protocol stack that said
predetermined, reserved physical address is reachable
through said pseudo network adapter, wherein said step of
indicating to said local communications protocol stack
modifies a data structure in said local communications
protocol stack indicating which nodes or networks are
reachable through each network interface of the local
system.
Claim 11
Dependent Claim
105 words
The method of claim 9, further comprising indicating
to said local communications protocol stack that one or
more nodes on a remote private network connected to said
remote server node are reachable through a gateway node
equal to said second pseudo network adapter on said remote
server node, wherein said step of indicating to said local
communications protocol stack that one or more nodes on
said remote private network connected to said remote server
node are reachable through a gateway node equal to said
second pseudo network adapter on said remote server node
modifies a network layer routing table in said local
communications protocol stack.
Claim 12
Dependent Claim
154 words
The method of claim 9, further comprising: processing data packets captured by said
interface for capturing packets from said local
communications protocol stack for transmission on said
virtual private network in a transmit data path; encrypting said data packets in an encryption
engine, within said transmit path; encapsulating said encrypted data packets into
tunnel data frames by an encapsulation engine, within
said transmit path; and passing said tunnel data frames back to said
local communications protocol stack for transmission
to a physical network adapter on said remote server
node, wherein said transmit path further includes
storing a digest value in a digest field in each of
said tunnel data frames, said digest value equal to an
output of a keyed hash function applied to said data
packet encapsulated within said tunnel data frame
concatenated with a counter value equal to a total
number of tunnel data frames previously transmitted to
said remote server node.
Claim 13
Dependent Claim
34 words
The method of claim 12, wherein said transmit path
further includes processing an Ethernet header in each one
of said captured data packets, said processing of said
Ethernet header including removing said Ethernet header.
Claim 14
Dependent Claim
114 words
The method of claim 9, further comprising
capturing received data packets from said remote server
node through an interface into a transport layer of said
local communications protocol stack, further comprising: processing received data packets captured by said
interface into said transport layer of said local
communications protocol stack for capturing received
data packets from said remote server node in a receive
path; decapsulating said received data packets by
removing a tunnel frame header in an decapsulation
engine, within said receive path; decrypting said received data packets in a
decryption engine within said receive path; and passing said received data frames packets back to
said local communications protocol stack for delivery
to a user.
Claim 15
Dependent Claim
41 words
The method of claim 9, wherein said network layer
address for said pseudo network adapter and said
predetermined, reserved physical address is communicated to
said pseudo network adapter from said remote server node as
client data in a connection response frame.
References Cited (Backward Citations)
No citation records indexed.
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