Local Area Networks (LANs) in Aircraft - FTP Directory Listing - FAA

More documents

Recommendations

Info

Both the PE and CE devices are normally either IP routers or label switching routers (i.e., the latter supports MPLS, and the former supports traditional IP IGP and EGP routing). The labels r3, r4, r5, and r6 in figure 34 represent IP routers that are internal to the customer site. The IPsec variant [99] of RFC 4364 that is used in this architecture is described as follows: “In BGP/MPLS IP Virtual Private Networks (VPNs), VPN data packets traveling from one Provider Edge (PE) router to another generally carry two MPLS labels, an “inner” label that corresponds to a VPN-specific route, and an “outer” label that corresponds to a Label Switched Path (LSP) between PE routers. In some circumstances, it is desirable to support the same type of VPN architecture, but using an IPsec Security Association in place of that LSP. The “outer” MPLS label would thus be replaced by an IP/IPsec header. This enables the VPN packets to be carried securely over non-MPLS networks, using standard IPsec authentication and/or encryption functions to protect them.” [99] r3 CE2 r5 r4 CE1 PE1 PE1 CE3 r6 Customer Site 1 Service Provider(s) Customer Site 2 Figure 34. The VPN Interconnecting Two Sites (copy of Figure 1.1 of RFC 4110) The specific implementation proposed in this report’s design has defined an encapsulation gateway middlebox (RFC 3234) that performs the functions of both the CE and PE interfaces of figure 34 for each specific software level VPN community. For example, if an airplane has four different software level communities, then there will be four distinct encapsulating gateway devices on that airplane, one for each software level community. The encapsulation gateway, therefore, operates exactly like the COMSEC device in figure 17 and the interface in figures 20 and 22. The VPN technology recommended by this study uses ubiquitously available IPsec technology. However, VPN scalability itself is achieved by adopting proven IETF L3VPN BGP/MPLS techniques. The IPsec variant of BGP/MPLS, which this study recommends, is not as widely deployed today as its BGP/MPLS parent technology. The deployments that do exist primarily (probably exclusively) implement the IPsec approach via routers. There are two reasons this study recommends developing an encapsulation gateway middlebox rather than 110
using the traditional dual router implementation of reference 99 currently deployed in the Internet today: • To reduce the SWAP footprint of the encapsulation upon aircraft. • To enable network management deployments where an entire airplane (e.g., multiple enclaves) can be managed from a single network management system (see section 8.4). It is probable that no middlebox implementation of this technology existed at the time this study was written. Creating a middlebox variant of this technology, therefore, represents a recommended development activity. Special care should be taken in the security design of its network management support capability (see section 8.4). Figure 30 shows that the encapsulating gateway that service Level A software networks on the airplane communicates with its peer encapsulation gateways servicing Level A networks on another airplane or on the ground via IPsec’s ESP in tunnel mode communications. Entities within the Level A networks use normal IP communications between themselves (i.e., plain text). From their perspective, they are using COTS IPs just like any other IP device would. They are unaware that any network exists outside of their own Level A enclave. They are also unaware that their enclave is using network services provided outside of their enclave (e.g., the network between the encapsulation gateways that service their enclave). VPN encryption and encapsulation is performed by their local encapsulation gateway so that no entity or network outside of their network enclave sees intraenclave communication except in its encrypted and encapsulated form. For example, from the point of view of the firewall in figure 30, communications from a Level A device on the airplane to a Level A device off of the airplane is merely an IP communication between two different encapsulation gateways (i.e., no entity outside of the VPN-protected enclave itself knows about the enclave). Therefore, the Level A VPN enclave entities have no knowledge about any entity outside of their own enclave community. The same is true for the Level B VPN enclave, the Level C VPN enclave, and so on—each VPN enclave only knows about itself. No entity outside of that enclave knows about entities inside a different enclave. Therefore, the enclave population is narrowly restricted to the members of the enclave only. Effective network partitioning has occurred. Even in the worst-case scenario where all firewalls in the entire NAS and on every airplane have become compromised and the airplanes are connected to the worldwide Internet, the enclave population remains restricted to the enclave membership only. Airplane passengers cannot communicate with devices inside an enclave (indeed, they do not know they exist) nor can any other entity outside of the enclave do so. Therefore, the risks articulated in section 4.1 have been mitigated. If there is no human presence in an enclave (i.e., if the enclave is solely populated by devices), then the risks articulated in section 4.2 have also been mitigated for that enclave. If both of these are the case, then the concerns mentioned in sections 4.3 and 4.4 persist at a diminished risk level because the threat agents that can directly attack VPN entities are now restricted to the device population of the VPN itself. (Note: defense-in-depth protections (e.g., QoS) are still needed to ensure that the LAN supporting the VPN is not attacked, which, if successful, could potentially result in DoS to the VPN.) Nevertheless, COTS devices are not 111
Page 1 and 2:
DOT/FAA/AR-08/31 Air Traffic Organi
Page 3 and 4:
1. Report No. DOT/FAA/AR-08/31 4. T
Page 5 and 6:
5.4.2 Aircraft as a Node (MIP and M
Page 7 and 8:
11.1 Findings and Recommendations 1
Page 9 and 10:
22 Customer’s L3VPN Protocol Stac
Page 11 and 12:
LIST OF ACRONYMS AND ABBREVIATIONS
Page 13 and 14:
PBN PC PE PEP PFS PIB PIM-DM PIM-SM
Page 15 and 16:
This report states that the primary
Page 17 and 18:
1. INTRODUCTION. This is the final
Page 19 and 20:
protocol (IP)-based communications.
Page 21 and 22:
of linking aircraft-resident system
Page 23 and 24:
Industry and governments are extrem
Page 25 and 26:
2.1 NOTIONAL NETWORKED AIRCRAFT ARC
Page 27 and 28:
Other Control Sites Controller ATC
Page 29 and 30:
• The security viability of curre
Page 31 and 32:
alternative requires that parallel
Page 33 and 34:
Aircraft network security is a syst
Page 35 and 36:
4. NETWORK RISKS. This section spec
Page 37 and 38:
General Threat Identifiers FAILURE
Page 39 and 40:
esources so that the required real-
Page 41 and 42:
“With the rise of client-side att
Page 43 and 44:
• During an 11-month period (Apri
Page 45 and 46:
attempt the theft of passwords. Non
Page 47 and 48:
IP networks are organized in terms
Page 49 and 50:
either the user or the trusted soft
Page 51 and 52:
However, the previous paragraph beg
Page 53 and 54:
Table 1. Internet Engineering Task
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
• Lightweight directory access pr
Page 61 and 62:
mechanism to overcome the key distr
Page 63 and 64:
Deployments that need to support mu
Page 65 and 66:
Today’s Reality: Islands of Commu
Page 67 and 68:
Simultaneously, IP addresses are al
Page 69 and 70:
in-depth manner. Defense-in-depth m
Page 71 and 72:
Protection Detection Reaction / Neu
Page 73 and 74:
encrypted and then encapsulated wit
Page 75 and 76: Internet (grouping of autonomous sy
Page 77 and 78: via that same IP address. Specifica
Page 79 and 80: deployments. Regional flights that
Page 81 and 82: neighbor as a next hop after “Hol
Page 83 and 84: Interface Interface Customer Site S
Page 85 and 86: Interface Customer’s Application
Page 87 and 88: Although the vast majority of PBN s
Page 89 and 90: 6. RELATING SAFETY AND SECURITY FOR
Page 91 and 92: 6.1.1 Integrity. As section 4.3 ind
Page 93 and 94: As mentioned in section 4.4, the hi
Page 95 and 96: 6.1.4 Confidentiality. Confidential
Page 97 and 98: their own classification level nor
Page 99 and 100: integrity is not permitted to obser
Page 101 and 102: software has been confirmed as leve
Page 103 and 104: • Both safety and security are co
Page 105 and 106: Device at Safety level X Device at
Page 107 and 108: in a Biba Integrity Model environme
Page 109 and 110: Common Criteria Classes ACM—Confi
Page 111 and 112: (see section 9.10). A secure mechan
Page 113 and 114: employed in security-critical appli
Page 115 and 116: concept, which is needed to create
Page 117 and 118: 4. Learn from past mistakes. Poor d
Page 119 and 120: exemplar airborne network architect
Page 121 and 122: • Requirement 8: Biba Integrity M
Page 123 and 124: Figure 31 shows how the recommended
Page 125: to-live (TTL) field in the IP heade
Page 129 and 130: mechanism relies upon the controlle
Page 131 and 132: HAGs are high-assurance devices tha
Page 133 and 134: 8.3.5 Firewall. The firewall needs
Page 135 and 136: (AJ) or low probability of intercep
Page 137 and 138: design decisions that need to be de
Page 139 and 140: 9.2 INTEGRATED MODULAR AVIONICS IMP
Page 141 and 142: 9.3 USING PUBLIC IPs. The model and
Page 143 and 144: alerted the pilots because the fail
Page 145 and 146: environments. If the certification
Page 147 and 148: DSS (FIPS 186 [81]). Code signing i
Page 149 and 150: elationship with other equipment in
Page 151 and 152: approach is to keep the log informa
Page 153 and 154: 11. SUMMARY. Current civilian aircr
Page 155 and 156: environments should be extended to
Page 157 and 158: 12. COTS computer systems cannot be
Page 159 and 160: 14. NAS and airborne network archit
Page 161 and 162: 22. If SWAP considerations permit,
Page 163 and 164: 11.2 TOPICS NEEDING FURTHER STUDY.
Page 165 and 166: 9. Lee, Y., Rachlin, E., and Scandu
Page 167 and 168: 32. Loscocco, P., Smalley, S., Muck
Page 169 and 170: 59. Raisinghani, V. and Sridhar, I.
Page 171 and 172: the following is a pointer to a rel
Page 173 and 174: Department of Defense Instruction N
Page 175 and 176: Information Assurance—The Departm
Page 177 and 178:
Threat source—Either (1) intent a
Page 179 and 180:
information found within these data
Page 181 and 182:
(HTTP) traffic (port 80), port scan
Page 183 and 184:
The simple network management proto
Page 185 and 186:
opportunities to crack the hosting
Page 187 and 188:
authorized to perform. 13 However,
Page 189 and 190:
sniffers, log-cleaning scripts, and
Page 191 and 192:
A.3.1 DENIAL OF SERVICE ATTACKS. Th
Page 193 and 194:
• Disclosure: Disclosure of routi
Page 195 and 196:
affected by the signal intermittenc
Page 197 and 198:
A-15. Barbir, A., Murphy, S., and Y
Page 199 and 200:
Survey Question What is the primary
Page 201 and 202:
Survey Question What is the primary
Page 203 and 204:
should be emphasized that there is
show all

Local Area Networks (LANs) in Aircraft - FTP Directory Listing - FAA

Create successful ePaper yourself

Delete template?

Save as template?