SN User's Guide - ESC Home - NASA

The Restricted IONet projects have a moderate degree of protection due to their
perimeter negotiations and access control via the Restricted IONet Firewall, but support
real-time mission-critical data. The Open IONet is intended to support the more liberal
needs of the science community, but on a 24x7 service level. The Open IONet provides
a modest level of protection with the implementation of the Open IONet Firewall that
requires all Open IONet customers to register the data flows with external IONet
customers. Customers may apply for connection to any of the domains as NISN
requirements analysis determine and the IONet Access Protection Policy and
Requirements, 290-004, dictate. This document uses the term IONet when referring to
all three networks. Otherwise, it specifies whether the material pertains specifically to
the Open, Restricted, or Closed IONet.
I.2.1.2 Legacy MDM/4800 Bit Block
The legacy interface is targeted for End-of-Life in the near future and as such, it is not
recommended that any new project interfaces be implemented on it. The replacement
interface has not been specified at this document’s time of publishing.
The legacy interface delivers and accepts data via IP multicast packets with 4800 bit
block formatted data units. Customers who use this interface must be connected via
the IP multicast-enabled part of IONet, which is also the most secured domain of the
IONet (see Figure I-1). Project interfaces are rigidly controlled and audited for this
service, according to the IONet Access Protection Policy and Requirements.
I.2.1.3 WDISC IP
The WDISC IP interface (please see Appendix Q for WDISC information) is supported
via Closed IONet interface (see Figure I-2 and the IONet Access Protection Policy and
Requirements). Because this interface is Unicast IP, it is possible to interface to it via
the IONet Secure Gateway System, from the Open IONet or beyond, as permitted in the
IONet Access Protection Policy and Requirements.
I.2.1.4 Space Network Access System (SNAS)
The SNAS (please see Appendix P for detailed SNAS information) is designed to be
accessed from the NISN Closed IONet or Open IONet (see Figure I-3). CSO’s NISN
Open IONet allows access from the NASA Science Internet (Restricted IONet) and the
public Internet, thus allowing cooperation with NASA's university, enterprise, and
inter/intra-agency partners.
I.2.1.5 SN Gateway
The SN Gateway IP interface (please see Appendix R for SN Gateway information) is
supported via Restricted IONet interface (see Figure I-4 and the IONet Access
Protection Policy and Requirements). The SN Gateway supports CCSDS SLE services,
which require customers to initiate SLE bind operations with the SN Gateway.
Customers on the Restricted IONet are allowed to make binds or TCP/IP connections
with the gateway.
Revision 10 I-2 450-SNUG