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 as described 17 in the PPP-HOWTO, available at 18 <http://www.tldp.org/docs.html#howto>. Make sure that you have 19 the version of pppd recommended in <file:Documentation/Changes>. 20 The PPP option enlarges your kernel by about 16 KB. 21 22 There are actually two versions of PPP: the traditional PPP for 23 asynchronous lines, such as regular analog phone lines, and 24 synchronous PPP which can be used over digital ISDN lines for 25 example. If you want to use PPP over phone lines or other 26 asynchronous serial lines, you need to say Y (or M) here and also to 27 the next option, "PPP support for async serial ports". For PPP over 28 synchronous lines, you should say Y (or M) here and to "Support 29 synchronous PPP", below. 30 31 If you said Y to "Version information on all symbols" above, then 32 you cannot compile the PPP driver into the kernel; you can then only 33 compile it as a module. To compile this driver as a module, choose M 34 here. The module will be called ppp_generic. 35 36if PPP 37 38config PPP_BSDCOMP 39 tristate "PPP BSD-Compress compression" 40 help 41 Support for the BSD-Compress compression method for PPP, which uses 42 the LZW compression method to compress each PPP packet before it is 43 sent over the wire. The machine at the other end of the PPP link 44 (usually your ISP) has to support the BSD-Compress compression 45 method as well for this to be useful. Even if they don't support it, 46 it is safe to say Y here. 47 48 The PPP Deflate compression method ("PPP Deflate compression", 49 above) is preferable to BSD-Compress, because it compresses better 50 and is patent-free. 51 52 Note that the BSD compression code will always be compiled as a 53 module; it is called bsd_comp and will show up in the directory 54 modules once you have said "make modules". If unsure, say N. 55 56config PPP_DEFLATE 57 tristate "PPP Deflate compression" 58 select ZLIB_INFLATE 59 select ZLIB_DEFLATE 60 help 61 Support for the Deflate compression method for PPP, which uses the 62 Deflate algorithm (the same algorithm that gzip uses) to compress 63 each PPP packet before it is sent over the wire. The machine at the 64 other end of the PPP link (usually your ISP) has to support the 65 Deflate compression method as well for this to be useful. Even if 66 they don't support it, it is safe to say Y here. 67 68 To compile this driver as a module, choose M here. 69 70config PPP_FILTER 71 bool "PPP filtering" 72 help 73 Say Y here if you want to be able to filter the packets passing over 74 PPP interfaces. This allows you to control which packets count as 75 activity (i.e. which packets will reset the idle timer or bring up 76 a demand-dialed link) and which packets are to be dropped entirely. 77 You need to say Y here if you wish to use the pass-filter and 78 active-filter options to pppd. 79 80 If unsure, say N. 81 82config PPP_MPPE 83 tristate "PPP MPPE compression (encryption)" 84 select CRYPTO_LIB_ARC4 85 select CRYPTO_LIB_SHA1 86 help 87 Support for the MPPE Encryption protocol, as employed by the 88 Microsoft Point-to-Point Tunneling Protocol. 89 90 See http://pptpclient.sourceforge.net/ for information on 91 configuring PPTP clients and servers to utilize this method. 92 93config PPP_MULTILINK 94 bool "PPP multilink support" 95 help 96 PPP multilink is a protocol (defined in RFC 1990) which allows you 97 to combine several (logical or physical) lines into one logical PPP 98 connection, so that you can utilize your full bandwidth. 99 100 This has to be supported at the other end as well and you need a 101 version of the pppd daemon which understands the multilink protocol. 102 103 If unsure, say N. 104 105config PPPOATM 106 tristate "PPP over ATM" 107 depends on ATM 108 help 109 Support PPP (Point to Point Protocol) encapsulated in ATM frames. 110 This implementation does not yet comply with section 8 of RFC2364, 111 which can lead to bad results if the ATM peer loses state and 112 changes its encapsulation unilaterally. 113 114config PPPOE 115 tristate "PPP over Ethernet" 116 help 117 Support for PPP over Ethernet. 118 119 This driver requires the latest version of pppd from the CVS 120 repository at cvs.samba.org. Alternatively, see the 121 RoaringPenguin package (<http://www.roaringpenguin.com/pppoe>) 122 which contains instruction on how to use this driver (under 123 the heading "Kernel mode PPPoE"). 124 125choice 126 prompt "Number of PPPoE hash bits" 127 default PPPOE_HASH_BITS_4 128 depends on PPPOE 129 help 130 Select the number of bits used for hashing PPPoE interfaces. 131 132 Larger sizes reduces the risk of hash collisions at the cost 133 of slightly increased memory usage. 134 135 This hash table is on a per outer ethernet interface. 136 137config PPPOE_HASH_BITS_1 138 bool "1 bit (2 buckets)" 139 140config PPPOE_HASH_BITS_2 141 bool "2 bits (4 buckets)" 142 143config PPPOE_HASH_BITS_4 144 bool "4 bits (16 buckets)" 145 146config PPPOE_HASH_BITS_8 147 bool "8 bits (256 buckets)" 148 149endchoice 150 151config PPPOE_HASH_BITS 152 int 153 default 1 if PPPOE_HASH_BITS_1 154 default 2 if PPPOE_HASH_BITS_2 155 default 4 if PPPOE_HASH_BITS_4 156 default 8 if PPPOE_HASH_BITS_8 157 default 4 158 159config PPTP 160 tristate "PPP over IPv4 (PPTP)" 161 depends on NET_IPGRE_DEMUX 162 help 163 Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) 164 165 This driver requires pppd plugin to work in client mode or 166 modified pptpd (poptop) to work in server mode. 167 See http://accel-pptp.sourceforge.net/ for information how to 168 utilize this module. 169 170config PPPOL2TP 171 tristate "PPP over L2TP" 172 depends on L2TP 173 help 174 Support for PPP-over-L2TP socket family. L2TP is a protocol 175 used by ISPs and enterprises to tunnel PPP traffic over UDP 176 tunnels. L2TP is replacing PPTP for VPN uses. 177if TTY 178 179config PPP_ASYNC 180 tristate "PPP support for async serial ports" 181 select CRC_CCITT 182 help 183 Say Y (or M) here if you want to be able to use PPP over standard 184 asynchronous serial ports, such as COM1 or COM2 on a PC. If you use 185 a modem (not a synchronous or ISDN modem) to contact your ISP, you 186 need this option. 187 188 To compile this driver as a module, choose M here. 189 190 If unsure, say Y. 191 192config PPP_SYNC_TTY 193 tristate "PPP support for sync tty ports" 194 help 195 Say Y (or M) here if you want to be able to use PPP over synchronous 196 (HDLC) tty devices, such as the SyncLink adapter. These devices 197 are often used for high-speed leased lines like T1/E1. 198 199 To compile this driver as a module, choose M here. 200 201endif # TTY 202 203endif # PPP 204