1# SPDX-License-Identifier: GPL-2.0-only 2# 3# PPP network device configuration 4# 5 6config PPP 7 tristate "PPP (point-to-point protocol) support" 8 select SLHC 9 help 10 PPP (Point to Point Protocol) is a newer and better SLIP. It serves 11 the same purpose: sending Internet traffic over telephone (and other 12 serial) lines. Ask your access provider if they support it, because 13 otherwise you can't use it; most Internet access providers these 14 days support PPP rather than SLIP. 15 16 To use PPP, you need an additional program called pppd, available at 17 <https://ppp.samba.org>. Make sure that you have the version of pppd 18 recommended in <file:Documentation/Changes>. 19 The PPP option enlarges your kernel by about 16 KB. 20 21 There are actually two versions of PPP: the traditional PPP for 22 asynchronous lines, such as regular analog phone lines, and 23 synchronous PPP which can be used over digital ISDN lines for 24 example. If you want to use PPP over phone lines or other 25 asynchronous serial lines, you need to say Y (or M) here and also to 26 the next option, "PPP support for async serial ports". For PPP over 27 synchronous lines, you should say Y (or M) here and to "Support 28 synchronous PPP", below. 29 30 If you said Y to "Version information on all symbols" above, then 31 you cannot compile the PPP driver into the kernel; you can then only 32 compile it as a module. To compile this driver as a module, choose M 33 here. The module will be called ppp_generic. 34 35if PPP 36 37config PPP_BSDCOMP 38 tristate "PPP BSD-Compress compression" 39 help 40 Support for the BSD-Compress compression method for PPP, which uses 41 the LZW compression method to compress each PPP packet before it is 42 sent over the wire. The machine at the other end of the PPP link 43 (usually your ISP) has to support the BSD-Compress compression 44 method as well for this to be useful. Even if they don't support it, 45 it is safe to say Y here. 46 47 The PPP Deflate compression method ("PPP Deflate compression", 48 above) is preferable to BSD-Compress, because it compresses better 49 and is patent-free. 50 51 Note that the BSD compression code will always be compiled as a 52 module; it is called bsd_comp and will show up in the directory 53 modules once you have said "make modules". If unsure, say N. 54 55config PPP_DEFLATE 56 tristate "PPP Deflate compression" 57 select ZLIB_INFLATE 58 select ZLIB_DEFLATE 59 help 60 Support for the Deflate compression method for PPP, which uses the 61 Deflate algorithm (the same algorithm that gzip uses) to compress 62 each PPP packet before it is sent over the wire. The machine at the 63 other end of the PPP link (usually your ISP) has to support the 64 Deflate compression method as well for this to be useful. Even if 65 they don't support it, it is safe to say Y here. 66 67 To compile this driver as a module, choose M here. 68 69config PPP_FILTER 70 bool "PPP filtering" 71 help 72 Say Y here if you want to be able to filter the packets passing over 73 PPP interfaces. This allows you to control which packets count as 74 activity (i.e. which packets will reset the idle timer or bring up 75 a demand-dialed link) and which packets are to be dropped entirely. 76 You need to say Y here if you wish to use the pass-filter and 77 active-filter options to pppd. 78 79 If unsure, say N. 80 81config PPP_MPPE 82 tristate "PPP MPPE compression (encryption)" 83 select CRYPTO_LIB_ARC4 84 select CRYPTO_LIB_SHA1 85 help 86 Support for the MPPE Encryption protocol, as employed by the 87 Microsoft Point-to-Point Tunneling Protocol. 88 89 See http://pptpclient.sourceforge.net/ for information on 90 configuring PPTP clients and servers to utilize this method. 91 92config PPP_MULTILINK 93 bool "PPP multilink support" 94 help 95 PPP multilink is a protocol (defined in RFC 1990) which allows you 96 to combine several (logical or physical) lines into one logical PPP 97 connection, so that you can utilize your full bandwidth. 98 99 This has to be supported at the other end as well and you need a 100 version of the pppd daemon which understands the multilink protocol. 101 102 If unsure, say N. 103 104config PPPOATM 105 tristate "PPP over ATM" 106 depends on ATM 107 help 108 Support PPP (Point to Point Protocol) encapsulated in ATM frames. 109 This implementation does not yet comply with section 8 of RFC2364, 110 which can lead to bad results if the ATM peer loses state and 111 changes its encapsulation unilaterally. 112 113config PPPOE 114 tristate "PPP over Ethernet" 115 help 116 Support for PPP over Ethernet. 117 118 To work in client mode, pppd version 2.4.2 or later is required. 119 To work in server mode, the pppoe-server command from the RP-PPPoE 120 package is also required, available at 121 <https://dianne.skoll.ca/projects/rp-pppoe/>. 122 123choice 124 prompt "Number of PPPoE hash bits" 125 default PPPOE_HASH_BITS_4 126 depends on PPPOE 127 help 128 Select the number of bits used for hashing PPPoE interfaces. 129 130 Larger sizes reduces the risk of hash collisions at the cost 131 of slightly increased memory usage. 132 133 This hash table is on a per outer ethernet interface. 134 135config PPPOE_HASH_BITS_1 136 bool "1 bit (2 buckets)" 137 138config PPPOE_HASH_BITS_2 139 bool "2 bits (4 buckets)" 140 141config PPPOE_HASH_BITS_4 142 bool "4 bits (16 buckets)" 143 144config PPPOE_HASH_BITS_8 145 bool "8 bits (256 buckets)" 146 147endchoice 148 149config PPPOE_HASH_BITS 150 int 151 default 1 if PPPOE_HASH_BITS_1 152 default 2 if PPPOE_HASH_BITS_2 153 default 4 if PPPOE_HASH_BITS_4 154 default 8 if PPPOE_HASH_BITS_8 155 default 4 156 157config PPTP 158 tristate "PPP over IPv4 (PPTP)" 159 depends on NET_IPGRE_DEMUX 160 help 161 Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) 162 163 This driver requires pppd plugin to work in client mode or 164 modified pptpd (poptop) to work in server mode. 165 See http://accel-pptp.sourceforge.net/ for information how to 166 utilize this module. 167 168config PPPOL2TP 169 tristate "PPP over L2TP" 170 depends on L2TP 171 help 172 Support for PPP-over-L2TP socket family. L2TP is a protocol 173 used by ISPs and enterprises to tunnel PPP traffic over UDP 174 tunnels. L2TP is replacing PPTP for VPN uses. 175if TTY 176 177config PPP_ASYNC 178 tristate "PPP support for async serial ports" 179 select CRC_CCITT 180 help 181 Say Y (or M) here if you want to be able to use PPP over standard 182 asynchronous serial ports, such as COM1 or COM2 on a PC. If you use 183 a modem (not a synchronous or ISDN modem) to contact your ISP, you 184 need this option. 185 186 To compile this driver as a module, choose M here. 187 188 If unsure, say Y. 189 190config PPP_SYNC_TTY 191 tristate "PPP support for sync tty ports" 192 help 193 Say Y (or M) here if you want to be able to use PPP over synchronous 194 (HDLC) tty devices, such as the SyncLink adapter. These devices 195 are often used for high-speed leased lines like T1/E1. 196 197 To compile this driver as a module, choose M here. 198 199endif # TTY 200 201endif # PPP 202