diff --git a/conf/confbase.Y b/conf/confbase.Y
index ed3c1e6e..cdbdf1ce 100644
--- a/conf/confbase.Y
+++ b/conf/confbase.Y
@@ -118,7 +118,7 @@ CF_DECLS
 %type <time> expr_us time
 %type <a> ipa
 %type <net> net_ip4_ net_ip4 net_ip6_ net_ip6 net_ip_ net_ip net_or_ipa
-%type <net_ptr> net_ net_any net_vpn4_ net_vpn6_ net_vpn_ net_roa4_ net_roa6_ net_roa_ net_ip6_sadr_ net_mpls_
+%type <net_ptr> net_ net_any net_vpn4_ net_vpn6_ net_vpn_ net_roa4_ net_roa6_ net_roa_ net_ip6_sadr_ net_mpls_ net_aspa_
 %type <mls> label_stack_start label_stack
 
 %type <t> text opttext
@@ -299,6 +299,12 @@ net_mpls_: MPLS NUM
   net_fill_mpls($$, $2);
 }
 
+net_aspa_: ASPA NUM
+{
+  $$ = cfg_alloc(sizeof(net_addr_aspa));
+  net_fill_aspa($$, $2);
+}
+
 net_ip_: net_ip4_ | net_ip6_ ;
 net_vpn_: net_vpn4_ | net_vpn6_ ;
 net_roa_: net_roa4_ | net_roa6_ ;
@@ -310,6 +316,7 @@ net_:
  | net_flow_
  | net_ip6_sadr_
  | net_mpls_
+ | net_aspa_
  ;
 
 
diff --git a/doc/bird.sgml b/doc/bird.sgml
index ced927d4..d0bfabdb 100644
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -5972,6 +5972,13 @@ options (<cf/bfd/ and <cf/weight 1/), the second nexthop has just <cf/weight 2/.
 
 <p>The ROA config is just <cf>route <m/prefix/ max <m/int/ as <m/int/</cf> with no nexthop.
 
+<sect1>Autonomous System Provider Authorization
+
+<p>The ASPA config is <cf>route aspa <m/int/ providers <m/int/ [, <m/int/ ...]</cf> with no nexthop.
+  The first ASN is client and the following are a list of providers.
+  For a transit, you can also write <cf>route aspa <m/int/ transit</cf> to get
+  the no-provider ASPA.
+
 <sect1>Flowspec
 <label id="flowspec-network-type">
 
diff --git a/lib/net.c b/lib/net.c
index 289a4297..76bb3e80 100644
--- a/lib/net.c
+++ b/lib/net.c
@@ -16,6 +16,7 @@ const char * const net_label[] = {
   [NET_FLOW6]	= "flow6",
   [NET_IP6_SADR]= "ipv6-sadr",
   [NET_MPLS]	= "mpls",
+  [NET_ASPA]	= "aspa",
 };
 
 const u16 net_addr_length[] = {
@@ -29,6 +30,7 @@ const u16 net_addr_length[] = {
   [NET_FLOW6]	= 0,
   [NET_IP6_SADR]= sizeof(net_addr_ip6_sadr),
   [NET_MPLS]	= sizeof(net_addr_mpls),
+  [NET_ASPA]	= sizeof(net_addr_aspa),
 };
 
 const u8 net_max_prefix_length[] = {
@@ -42,6 +44,7 @@ const u8 net_max_prefix_length[] = {
   [NET_FLOW6]	= IP6_MAX_PREFIX_LENGTH,
   [NET_IP6_SADR]= IP6_MAX_PREFIX_LENGTH,
   [NET_MPLS]	= 0,
+  [NET_ASPA]	= 0,
 };
 
 const u16 net_max_text_length[] = {
@@ -55,6 +58,7 @@ const u16 net_max_text_length[] = {
   [NET_FLOW6]	= 0,	/* "flow6 { ... }" */
   [NET_IP6_SADR]= 92,	/* "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128 from ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128" */
   [NET_MPLS]	= 7,	/* "1048575" */
+  [NET_ASPA]	= 10,	/* "4294967295" */
 };
 
 /* There should be no implicit padding in net_addr structures */
@@ -69,6 +73,7 @@ STATIC_ASSERT(sizeof(net_addr_flow4)	==  8);
 STATIC_ASSERT(sizeof(net_addr_flow6)	== 20);
 STATIC_ASSERT(sizeof(net_addr_ip6_sadr)	== 40);
 STATIC_ASSERT(sizeof(net_addr_mpls)	==  8);
+STATIC_ASSERT(sizeof(net_addr_aspa)	==  8);
 
 
 int
@@ -123,6 +128,8 @@ net_format(const net_addr *N, char *buf, int buflen)
     return bsnprintf(buf, buflen, "%I6/%d from %I6/%d", n->ip6_sadr.dst_prefix, n->ip6_sadr.dst_pxlen, n->ip6_sadr.src_prefix, n->ip6_sadr.src_pxlen);
   case NET_MPLS:
     return bsnprintf(buf, buflen, "%u", n->mpls.label);
+  case NET_ASPA:
+    return bsnprintf(buf, buflen, "%u", n->aspa.asn);
   }
 
   bug("unknown network type");
@@ -147,6 +154,7 @@ net_pxmask(const net_addr *a)
     return ipa_from_ip6(ip6_mkmask(net6_pxlen(a)));
 
   case NET_MPLS:
+  case NET_ASPA:
   default:
     return IPA_NONE;
   }
@@ -180,6 +188,8 @@ net_compare(const net_addr *a, const net_addr *b)
     return net_compare_ip6_sadr((const net_addr_ip6_sadr *) a, (const net_addr_ip6_sadr *) b);
   case NET_MPLS:
     return net_compare_mpls((const net_addr_mpls *) a, (const net_addr_mpls *) b);
+  case NET_ASPA:
+    return net_compare_aspa((const net_addr_aspa *) a, (const net_addr_aspa *) b);
   }
   return 0;
 }
@@ -201,6 +211,7 @@ net_hash(const net_addr *n)
   case NET_FLOW6: return NET_HASH(n, flow6);
   case NET_IP6_SADR: return NET_HASH(n, ip6_sadr);
   case NET_MPLS: return NET_HASH(n, mpls);
+  case NET_ASPA: return NET_HASH(n, aspa);
   default: bug("invalid type");
   }
 }
@@ -223,6 +234,7 @@ net_validate(const net_addr *n)
   case NET_FLOW6: return NET_VALIDATE(n, flow6);
   case NET_IP6_SADR: return NET_VALIDATE(n, ip6_sadr);
   case NET_MPLS: return NET_VALIDATE(n, mpls);
+  case NET_ASPA: return NET_VALIDATE(n, aspa);
   default: return 0;
   }
 }
@@ -250,6 +262,7 @@ net_normalize(net_addr *N)
     return net_normalize_ip6_sadr(&n->ip6_sadr);
 
   case NET_MPLS:
+  case NET_ASPA:
     return;
   }
 }
@@ -277,6 +290,7 @@ net_classify(const net_addr *N)
     return ip6_zero(n->ip6_sadr.dst_prefix) ? (IADDR_HOST | SCOPE_UNIVERSE) : ip6_classify(&n->ip6_sadr.dst_prefix);
 
   case NET_MPLS:
+  case NET_ASPA:
     return IADDR_HOST | SCOPE_UNIVERSE;
   }
 
@@ -310,6 +324,7 @@ ipa_in_netX(const ip_addr a, const net_addr *n)
 			    ip6_mkmask(net6_pxlen(n))));
 
   case NET_MPLS:
+  case NET_ASPA:
   default:
     return 0;
   }
diff --git a/lib/net.h b/lib/net.h
index e9828557..18788f8d 100644
--- a/lib/net.h
+++ b/lib/net.h
@@ -23,7 +23,8 @@
 #define NET_FLOW6	8
 #define NET_IP6_SADR	9
 #define NET_MPLS	10
-#define NET_MAX		11
+#define NET_ASPA	11
+#define NET_MAX		12
 
 #define NB_IP4		(1 << NET_IP4)
 #define NB_IP6		(1 << NET_IP6)
@@ -35,6 +36,7 @@
 #define NB_FLOW6	(1 << NET_FLOW6)
 #define NB_IP6_SADR	(1 << NET_IP6_SADR)
 #define NB_MPLS		(1 << NET_MPLS)
+#define NB_ASPA		(1 << NET_ASPA)
 
 #define NB_IP		(NB_IP4 | NB_IP6)
 #define NB_VPN		(NB_VPN4 | NB_VPN6)
@@ -124,6 +126,13 @@ typedef struct net_addr_mpls {
   u32 label;
 } net_addr_mpls;
 
+typedef struct net_addr_aspa {
+  u8 type;
+  u8 pxlen;
+  u16 length;
+  u32 asn;
+} net_addr_aspa;
+
 typedef struct net_addr_ip6_sadr {
   u8 type;
   u8 dst_pxlen;
@@ -145,6 +154,7 @@ typedef union net_addr_union {
   net_addr_flow6 flow6;
   net_addr_ip6_sadr ip6_sadr;
   net_addr_mpls mpls;
+  net_addr_aspa aspa;
 } net_addr_union;
 
 
@@ -183,6 +193,12 @@ extern const u16 net_max_text_length[];
 #define NET_ADDR_IP6_SADR(dst_prefix,dst_pxlen,src_prefix,src_pxlen) \
   ((net_addr_ip6_sadr) { NET_IP6_SADR, dst_pxlen, sizeof(net_addr_ip6_sadr), dst_prefix, src_pxlen, src_prefix })
 
+#define NET_ADDR_ASPA(asn) \
+  ((net_addr_aspa) { NET_ASPA, 32, sizeof(net_addr_aspa), asn })
+
+#define NET_ADDR_ASPA_EXISTS(asn) NET_ADDR_ASPA(asn, asn)
+#define NET_ADDR_ASPA_TRANSIT(asn) NET_ADDR_ASPA(asn, 0)
+
 #define NET_ADDR_MPLS(label) \
   ((net_addr_mpls) { NET_MPLS, 20, sizeof(net_addr_mpls), label })
 
@@ -211,6 +227,9 @@ static inline void net_fill_ip6_sadr(net_addr *a, ip6_addr dst_prefix, uint dst_
 static inline void net_fill_mpls(net_addr *a, u32 label)
 { *(net_addr_mpls *)a = NET_ADDR_MPLS(label); }
 
+static inline void net_fill_aspa(net_addr *a, u32 asn)
+{ *(net_addr_aspa *)a = NET_ADDR_ASPA(asn); }
+
 static inline void net_fill_ipa(net_addr *a, ip_addr prefix, uint pxlen)
 {
   if (ipa_is_ip4(prefix))
@@ -269,6 +288,9 @@ static inline int net_is_roa(const net_addr *a)
 static inline int net_is_flow(const net_addr *a)
 { return (a->type == NET_FLOW4) || (a->type == NET_FLOW6); }
 
+static inline int net_is_aspa(const net_addr *a)
+{ return (a->type == NET_ASPA); }
+
 static inline int net_is_sadr(const net_addr *a)
 { return (a->type == NET_IP6_SADR); }
 
@@ -296,6 +318,7 @@ static inline ip_addr net_prefix(const net_addr *a)
     return ipa_from_ip6(net6_prefix(a));
 
   case NET_MPLS:
+  case NET_ASPA:
   default:
     return IPA_NONE;
   }
@@ -366,6 +389,9 @@ static inline int net_equal_ip6_sadr(const net_addr_ip6_sadr *a, const net_addr_
 static inline int net_equal_mpls(const net_addr_mpls *a, const net_addr_mpls *b)
 { return !memcmp(a, b, sizeof(net_addr_mpls)); }
 
+static inline int net_equal_aspa(const net_addr_aspa *a, const net_addr_aspa *b)
+{ return !memcmp(a, b, sizeof(net_addr_aspa)); }
+
 
 static inline int net_equal_prefix_roa4(const net_addr_roa4 *a, const net_addr_roa4 *b)
 { return ip4_equal(a->prefix, b->prefix) && (a->pxlen == b->pxlen); }
@@ -407,6 +433,9 @@ static inline int net_zero_flow6(const net_addr_flow6 *a)
 static inline int net_zero_mpls(const net_addr_mpls *a)
 { return !a->label; }
 
+static inline int net_zero_aspa(const net_addr_aspa *a)
+{ return !a->asn; }
+
 
 static inline int net_compare_ip4(const net_addr_ip4 *a, const net_addr_ip4 *b)
 { return ip4_compare(a->prefix, b->prefix) ?: uint_cmp(a->pxlen, b->pxlen); }
@@ -442,6 +471,9 @@ static inline int net_compare_ip6_sadr(const net_addr_ip6_sadr *a, const net_add
 static inline int net_compare_mpls(const net_addr_mpls *a, const net_addr_mpls *b)
 { return uint_cmp(a->label, b->label); }
 
+static inline int net_compare_aspa(const net_addr_aspa *a, const net_addr_aspa *b)
+{ return uint_cmp(a->asn, b->asn); }
+
 int net_compare(const net_addr *a, const net_addr *b);
 
 
@@ -478,6 +510,9 @@ static inline void net_copy_ip6_sadr(net_addr_ip6_sadr *dst, const net_addr_ip6_
 static inline void net_copy_mpls(net_addr_mpls *dst, const net_addr_mpls *src)
 { memcpy(dst, src, sizeof(net_addr_mpls)); }
 
+static inline void net_copy_aspa(net_addr_aspa *dst, const net_addr_aspa *src)
+{ memcpy(dst, src, sizeof(net_addr_aspa)); }
+
 
 static inline u32 px4_hash(ip4_addr prefix, u32 pxlen)
 { return ip4_hash(prefix) ^ (pxlen << 26); }
@@ -521,6 +556,9 @@ static inline u32 net_hash_ip6_sadr(const net_addr_ip6_sadr *n)
 static inline u32 net_hash_mpls(const net_addr_mpls *n)
 { return u32_hash(n->label); }
 
+static inline u32 net_hash_aspa(const net_addr_aspa *n)
+{ return u32_hash(n->asn); }
+
 u32 net_hash(const net_addr *a);
 
 
@@ -570,6 +608,9 @@ static inline int net_validate_flow6(const net_addr_flow6 *n)
 static inline int net_validate_mpls(const net_addr_mpls *n)
 { return n->label < (1 << 20); }
 
+static inline int net_validate_aspa(const net_addr_aspa *n)
+{ return n->asn > 0; }
+
 static inline int net_validate_ip6_sadr(const net_addr_ip6_sadr *n)
 { return net_validate_px6(n->dst_prefix, n->dst_pxlen) && net_validate_px6(n->src_prefix, n->src_pxlen); }
 
diff --git a/nest/a-set.c b/nest/a-set.c
index 40ed573c..e84d7058 100644
--- a/nest/a-set.c
+++ b/nest/a-set.c
@@ -34,7 +34,7 @@
  * the buffer to indicate truncation.
  */
 int
-int_set_format(const struct adata *set, int way, int from, byte *buf, uint size)
+int_set_format(const struct adata *set, enum isf_way way, int from, byte *buf, uint size)
 {
   u32 *z = (u32 *) set->data;
   byte *end = buf + size - 24;
@@ -56,10 +56,18 @@ int_set_format(const struct adata *set, int way, int from, byte *buf, uint size)
       if (i > from2)
 	*buf++ = ' ';
 
-      if (way)
-	buf += bsprintf(buf, "(%d,%d)", z[i] >> 16, z[i] & 0xffff);
-      else
-	buf += bsprintf(buf, "%R", z[i]);
+      switch (way)
+      {
+	case ISF_COMMUNITY_LIST:
+	  buf += bsprintf(buf, "(%d,%d)", z[i] >> 16, z[i] & 0xffff);
+	  break;
+	case ISF_ROUTER_ID:
+	  buf += bsprintf(buf, "%R", z[i]);
+	  break;
+	case ISF_NUMBERS:
+	  buf += bsprintf(buf, "%u", z[i]);
+	  break;
+      }
     }
   *buf = 0;
   return 0;
diff --git a/nest/a-set_test.c b/nest/a-set_test.c
index 904e6764..c52b1d49 100644
--- a/nest/a-set_test.c
+++ b/nest/a-set_test.c
@@ -92,11 +92,11 @@ t_set_int_union(void)
   const struct adata *set_union;
   set_union = int_set_union(tmp_linpool, set_sequence, set_sequence_same);
   bt_assert(int_set_get_size(set_union) == SET_SIZE);
-  bt_assert(int_set_format(set_union, 0, 2, buf, BUFFER_SIZE) == 0);
+  bt_assert(int_set_format(set_union, ISF_ROUTER_ID, 2, buf, BUFFER_SIZE) == 0);
 
   set_union = int_set_union(tmp_linpool, set_sequence, set_sequence_higher);
   bt_assert_msg(int_set_get_size(set_union) == SET_SIZE*2, "int_set_get_size(set_union) %d, SET_SIZE*2 %d", int_set_get_size(set_union), SET_SIZE*2);
-  bt_assert(int_set_format(set_union, 0, 2, buf, BUFFER_SIZE) == 0);
+  bt_assert(int_set_format(set_union, ISF_ROUTER_ID, 2, buf, BUFFER_SIZE) == 0);
 
   return 1;
 }
@@ -106,17 +106,21 @@ t_set_int_format(void)
 {
   generate_set_sequence(SET_TYPE_INT, SET_SIZE_FOR_FORMAT_OUTPUT);
 
-  bt_assert(int_set_format(set_sequence, 0, 0, buf, BUFFER_SIZE) == 0);
+  bt_assert(int_set_format(set_sequence, ISF_ROUTER_ID, 0, buf, BUFFER_SIZE) == 0);
   bt_assert(strcmp(buf, "0.0.0.0 0.0.0.1 0.0.0.2 0.0.0.3 0.0.0.4 0.0.0.5 0.0.0.6 0.0.0.7 0.0.0.8 0.0.0.9") == 0);
 
   bzero(buf, BUFFER_SIZE);
-  bt_assert(int_set_format(set_sequence, 0, 2, buf, BUFFER_SIZE) == 0);
+  bt_assert(int_set_format(set_sequence, ISF_ROUTER_ID, 2, buf, BUFFER_SIZE) == 0);
   bt_assert(strcmp(buf, "0.0.0.2 0.0.0.3 0.0.0.4 0.0.0.5 0.0.0.6 0.0.0.7 0.0.0.8 0.0.0.9") == 0);
 
   bzero(buf, BUFFER_SIZE);
-  bt_assert(int_set_format(set_sequence, 1, 0, buf, BUFFER_SIZE) == 0);
+  bt_assert(int_set_format(set_sequence, ISF_COMMUNITY_LIST, 0, buf, BUFFER_SIZE) == 0);
   bt_assert(strcmp(buf, "(0,0) (0,1) (0,2) (0,3) (0,4) (0,5) (0,6) (0,7) (0,8) (0,9)") == 0);
 
+  bzero(buf, BUFFER_SIZE);
+  bt_assert(int_set_format(set_sequence, ISF_NUMBERS, 0, buf, BUFFER_SIZE) == 0);
+  bt_assert(strcmp(buf, "0 1 2 3 4 5 6 7 8 9") == 0);
+
   return 1;
 }
 
diff --git a/nest/attrs.h b/nest/attrs.h
index aee3468b..8b13e7a4 100644
--- a/nest/attrs.h
+++ b/nest/attrs.h
@@ -206,8 +206,13 @@ static inline int lc_match(const u32 *l, int i, lcomm v)
 static inline u32 *lc_copy(u32 *dst, const u32 *src)
 { memcpy(dst, src, LCOMM_LENGTH); return dst + 3; }
 
+enum isf_way {
+  ISF_NUMBERS,
+  ISF_COMMUNITY_LIST,
+  ISF_ROUTER_ID,
+};
 
-int int_set_format(const struct adata *set, int way, int from, byte *buf, uint size);
+int int_set_format(const struct adata *set, enum isf_way way, int from, byte *buf, uint size);
 int ec_format(byte *buf, u64 ec);
 int ec_set_format(const struct adata *set, int from, byte *buf, uint size);
 int lc_format(byte *buf, lcomm lc);
diff --git a/nest/config.Y b/nest/config.Y
index 20186ece..5d2f8d99 100644
--- a/nest/config.Y
+++ b/nest/config.Y
@@ -115,7 +115,7 @@ CF_DECLS
 
 CF_KEYWORDS(ROUTER, ID, HOSTNAME, PROTOCOL, TEMPLATE, PREFERENCE, DISABLED, DEBUG, ALL, OFF, DIRECT)
 CF_KEYWORDS(INTERFACE, IMPORT, EXPORT, FILTER, NONE, VRF, DEFAULT, TABLE, TABLES, STATES, ROUTES, FILTERS)
-CF_KEYWORDS(IPV4, IPV6, VPN4, VPN6, ROA4, ROA6, FLOW4, FLOW6, SADR, MPLS)
+CF_KEYWORDS(IPV4, IPV6, VPN4, VPN6, ROA4, ROA6, FLOW4, FLOW6, SADR, MPLS, ASPA)
 CF_KEYWORDS(RECEIVE, LIMIT, ACTION, WARN, BLOCK, RESTART, DISABLE, KEEP, FILTERED, RPKI)
 CF_KEYWORDS(PASSWORD, KEY, FROM, PASSIVE, TO, ID, EVENTS, PACKETS, PROTOCOLS, CHANNELS, INTERFACES)
 CF_KEYWORDS(ALGORITHM, KEYED, HMAC, MD5, SHA1, SHA256, SHA384, SHA512, BLAKE2S128, BLAKE2S256, BLAKE2B256, BLAKE2B512)
@@ -128,9 +128,10 @@ CF_KEYWORDS(MIN, IDLE, RX, TX, INTERVAL, MULTIPLIER, PASSIVE)
 CF_KEYWORDS(CHECK, LINK)
 CF_KEYWORDS(SORTED, TRIE, MIN, MAX, SETTLE, TIME, GC, THRESHOLD, PERIOD)
 CF_KEYWORDS(MPLS_LABEL, MPLS_POLICY, MPLS_CLASS)
+CF_KEYWORDS(ASPA_PROVIDERS)
 
 /* For r_args_channel */
-CF_KEYWORDS(IPV4, IPV4_MC, IPV4_MPLS, IPV6, IPV6_MC, IPV6_MPLS, IPV6_SADR, VPN4, VPN4_MC, VPN4_MPLS, VPN6, VPN6_MC, VPN6_MPLS, ROA4, ROA6, FLOW4, FLOW6, MPLS, PRI, SEC)
+CF_KEYWORDS(IPV4, IPV4_MC, IPV4_MPLS, IPV6, IPV6_MC, IPV6_MPLS, IPV6_SADR, VPN4, VPN4_MC, VPN4_MPLS, VPN6, VPN6_MC, VPN6_MPLS, ROA4, ROA6, FLOW4, FLOW6, MPLS, PRI, SEC, ASPA)
 
 CF_ENUM(T_ENUM_RTS, RTS_, STATIC, INHERIT, DEVICE, STATIC_DEVICE, REDIRECT,
 	RIP, OSPF, OSPF_IA, OSPF_EXT1, OSPF_EXT2, BGP, PIPE, BABEL, RPKI, L3VPN,
@@ -202,6 +203,7 @@ net_type_base:
  | ROA6 { $$ = NET_ROA6; }
  | FLOW4{ $$ = NET_FLOW4; }
  | FLOW6{ $$ = NET_FLOW6; }
+ | ASPA { $$ = NET_ASPA; }
  ;
 
 net_type:
@@ -209,7 +211,7 @@ net_type:
  | MPLS { $$ = NET_MPLS; }
  ;
 
-CF_ENUM(T_ENUM_NETTYPE, NET_, IP4, IP6, VPN4, VPN6, ROA4, ROA6, FLOW4, FLOW6, IP6_SADR, MPLS)
+CF_ENUM(T_ENUM_NETTYPE, NET_, IP4, IP6, VPN4, VPN6, ROA4, ROA6, FLOW4, FLOW6, IP6_SADR, MPLS, ASPA)
 
 
 /* Creation of routing tables */
@@ -840,6 +842,7 @@ channel_sym:
  | FLOW4	{ $$ = "flow4"; }
  | FLOW6	{ $$ = "flow6"; }
  | MPLS		{ $$ = "mpls"; }
+ | ASPA		{ $$ = "aspa"; }
  | PRI		{ $$ = "pri"; }
  | SEC		{ $$ = "sec"; }
  ;
@@ -972,6 +975,8 @@ proto_patt2:
 
 dynamic_attr: IGP_METRIC { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_GEN_IGP_METRIC); } ;
 
+dynamic_attr: ASPA_PROVIDERS { $$ = f_new_dynamic_attr(EAF_TYPE_INT_SET, T_CLIST, EA_ASPA_PROVIDERS); } ;
+
 dynamic_attr: MPLS_LABEL  { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_MPLS_LABEL); } ;
 dynamic_attr: MPLS_POLICY { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_ENUM_MPLS_POLICY, EA_MPLS_POLICY); } ;
 dynamic_attr: MPLS_CLASS  { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_MPLS_CLASS); } ;
diff --git a/nest/route.h b/nest/route.h
index 659783a8..9140b9e1 100644
--- a/nest/route.h
+++ b/nest/route.h
@@ -536,6 +536,7 @@ const char *ea_custom_name(uint ea);
 #define EA_MPLS_LABEL		EA_CODE(PROTOCOL_NONE, 1)
 #define EA_MPLS_POLICY		EA_CODE(PROTOCOL_NONE, 2)
 #define EA_MPLS_CLASS		EA_CODE(PROTOCOL_NONE, 3)
+#define EA_ASPA_PROVIDERS	EA_CODE(PROTOCOL_NONE, 4)
 
 #define EA_CODE_MASK 0xffff
 #define EA_CUSTOM_BIT 0x8000
diff --git a/nest/rt-attr.c b/nest/rt-attr.c
index c8ef8e08..09176632 100644
--- a/nest/rt-attr.c
+++ b/nest/rt-attr.c
@@ -823,8 +823,10 @@ ea_free(ea_list *o)
 }
 
 static int
-get_generic_attr(const eattr *a, byte **buf, int buflen UNUSED)
+get_generic_attr(const eattr *a, byte **buf, int buflen)
 {
+  byte *end = (*buf) + buflen;
+
   switch (a->id)
   {
   case EA_GEN_IGP_METRIC:
@@ -843,6 +845,13 @@ get_generic_attr(const eattr *a, byte **buf, int buflen UNUSED)
     *buf += bsprintf(*buf, "mpls_class");
     return GA_NAME;
 
+  case EA_ASPA_PROVIDERS:
+    *buf += bsprintf(*buf, "aspa_providers");
+    *(*buf)++ = ':';
+    *(*buf)++ = ' ';
+    *buf += int_set_format(a->u.ptr, ISF_NUMBERS, -1, *buf, end - *buf);
+    return GA_FULL;
+
   default:
     return GA_UNKNOWN;
   }
@@ -1007,7 +1016,7 @@ ea_show(struct cli *c, const eattr *e)
 	  bsprintf(pos, "%08x", e->u.data);
 	  break;
 	case EAF_TYPE_INT_SET:
-	  ea_show_int_set(c, ad, 1, pos, buf, end);
+	  ea_show_int_set(c, ad, ISF_COMMUNITY_LIST, pos, buf, end);
 	  return;
 	case EAF_TYPE_EC_SET:
 	  ea_show_ec_set(c, ad, pos, buf, end);
diff --git a/nest/rt-fib.c b/nest/rt-fib.c
index 43e3039d..688d0b96 100644
--- a/nest/rt-fib.c
+++ b/nest/rt-fib.c
@@ -279,6 +279,7 @@ fib_find(struct fib *f, const net_addr *a)
   case NET_FLOW6: return FIB_FIND(f, a, flow6);
   case NET_IP6_SADR: return FIB_FIND(f, a, ip6_sadr);
   case NET_MPLS: return FIB_FIND(f, a, mpls);
+  case NET_ASPA: return FIB_FIND(f, a, aspa);
   default: bug("invalid type");
   }
 }
@@ -300,6 +301,7 @@ fib_insert(struct fib *f, const net_addr *a, struct fib_node *e)
   case NET_FLOW6: FIB_INSERT(f, a, e, flow6); return;
   case NET_IP6_SADR: FIB_INSERT(f, a, e, ip6_sadr); return;
   case NET_MPLS: FIB_INSERT(f, a, e, mpls); return;
+  case NET_ASPA: FIB_INSERT(f, a, e, aspa); return;
   default: bug("invalid type");
   }
 }
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 85646647..5bd05fb2 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -690,7 +690,7 @@ static void
 bgp_format_cluster_list(const eattr *a, byte *buf, uint size)
 {
   /* Truncates cluster lists larger than buflen, probably not a problem */
-  int_set_format(a->u.ptr, 0, -1, buf, size);
+  int_set_format(a->u.ptr, ISF_ROUTER_ID, -1, buf, size);
 }
 
 
diff --git a/proto/static/config.Y b/proto/static/config.Y
index f1825edf..58d22d3a 100644
--- a/proto/static/config.Y
+++ b/proto/static/config.Y
@@ -15,6 +15,7 @@ CF_DEFINES
 #define STATIC_CFG ((struct static_config *) this_proto)
 static struct static_route *this_srt, *this_snh;
 static struct f_inst *this_srt_cmds, *this_srt_last_cmd;
+static uint this_srt_aspa_max;
 
 static struct static_route *
 static_nexthop_new(void)
@@ -47,6 +48,7 @@ CF_DECLS
 
 CF_KEYWORDS(STATIC, ROUTE, VIA, DROP, REJECT, PROHIBIT, PREFERENCE, CHECK, LINK, DEV)
 CF_KEYWORDS(ONLINK, WEIGHT, RECURSIVE, IGP, TABLE, BLACKHOLE, UNREACHABLE, BFD, MPLS)
+CF_KEYWORDS(TRANSIT, PROVIDERS)
 
 
 CF_GRAMMAR
@@ -148,8 +150,35 @@ stat_route:
  | stat_route0 BLACKHOLE	{ this_srt->dest = RTD_BLACKHOLE; }
  | stat_route0 UNREACHABLE	{ this_srt->dest = RTD_UNREACHABLE; }
  | stat_route0 PROHIBIT		{ this_srt->dest = RTD_PROHIBIT; }
+ | stat_route0 PROVIDER {
+    if (this_srt->net->type != NET_ASPA) cf_error("Provider settings available only for ASPA");
+    this_srt->aspa = cfg_alloc(sizeof (adata) + (this_srt_aspa_max = 8) * sizeof (u32));
+    this_srt->aspa->length = 0;
+   } stat_aspa_providers
+ | stat_route0 TRANSIT {
+    if (this_srt->net->type != NET_ASPA) cf_error("Transit settings available only for ASPA");
+    /* Allocate an explicit zero */
+    this_srt->aspa = cfg_alloc(sizeof (adata) + sizeof (u32));
+    this_srt->aspa->length = sizeof(u32);
+    ((u32 *) this_srt->aspa->data)[0] = 0;
+   }
  ;
 
+stat_aspa_provider: NUM {
+  if (this_srt->aspa->length == this_srt_aspa_max * sizeof(u32))
+  {
+    adata *new = cfg_alloc(sizeof (adata) + (this_srt_aspa_max * 2) * sizeof (u32));
+    memcpy(new, this_srt->aspa, this_srt->aspa->length + sizeof(adata));
+    this_srt->aspa = new;
+    this_srt_aspa_max *= 2;
+  }
+
+  ((u32 *) this_srt->aspa->data)[this_srt->aspa->length / sizeof(u32)] = $1;
+  this_srt->aspa->length += sizeof(u32);
+}
+
+stat_aspa_providers: stat_aspa_provider | stat_aspa_providers ',' stat_aspa_provider ;
+
 stat_route_item:
    cmd {
      if (this_srt_last_cmd)
diff --git a/proto/static/static.c b/proto/static/static.c
index 071803a8..661d04aa 100644
--- a/proto/static/static.c
+++ b/proto/static/static.c
@@ -99,6 +99,32 @@ static_announce_rte(struct static_proto *p, struct static_route *r)
     rta_set_recursive_next_hop(p->p.main_channel->table, a, tab, r->via, IPA_NONE, r->mls);
   }
 
+  if (r->net->type == NET_ASPA)
+  {
+    if (r->dest != RTD_NONE)
+    {
+      log(L_WARN "%s: ASPA %u configured with nexthop, ignoring the nexthop",
+	p->p.name, ((struct net_addr_aspa *) r->net)->asn);
+      r->dest = RTD_NONE;
+    }
+
+    if (!r->aspa)
+    {
+      log(L_WARN "%s: ASPA %u configured with no provider list, ignoring the whole rule",
+	p->p.name, ((struct net_addr_aspa *) r->net)->asn);
+      goto withdraw;
+    }
+
+    ea_list *ea = alloca(sizeof(ea_list) + sizeof(eattr));
+    *ea = (ea_list) { .flags = EALF_SORTED, .count = 1, .next = a->eattrs, };
+    ea->attrs[0] = (eattr) {
+      .id = EA_ASPA_PROVIDERS,
+      .type = EAF_TYPE_INT_SET,
+      .u.ptr = r->aspa,
+    };
+    a->eattrs = ea;
+  }
+
   if (p->p.mpls_channel)
   {
     struct mpls_channel *mc = (void *) p->p.mpls_channel;
diff --git a/proto/static/static.h b/proto/static/static.h
index a0a95a4b..edd2dc22 100644
--- a/proto/static/static.h
+++ b/proto/static/static.h
@@ -50,7 +50,10 @@ struct static_route {
   byte use_bfd;				/* Configured to use BFD */
   uint mpls_label;			/* Local MPLS label, -1 if unused */
   struct bfd_request *bfd_req;		/* BFD request, if BFD is used */
-  mpls_label_stack *mls;		/* MPLS label stack; may be NULL */
+  union {
+    mpls_label_stack *mls;		/* MPLS label stack; may be NULL */
+    adata *aspa;			/* ASPA provider list; may be NULL */
+  };
 };
 
 /*